|Portrayed by||Jessie Wallace|
|Spin-off Appearances|| Slaters in Detention |
|First Appearance||18 September 2000|
|Duration||2000–2005, 2010–2016, 2018-|
|Address||31 Albert Square|
|Date of Birth||14 January 1970|
Kat arrives in Walford on 18 September 2000, along with her family: father Charlie, sisters Lynne, Little Mo and Zoe, and grandmother Mo Harris. Kat embarks on a brief fling with Steve Owen, much to the annoyance of his girlfriend Mel Healy. She finds work in The Queen Victoria public house as a barmaid, where she is an instant hit with the customers. Fiercely defensive of her sisters, Kat embarks on a feud with Little Mo's abusive husband Trevor Morgan - though has a fling with Lynne's boyfriend Garry Hobbs. Much to Zoe's frustration, Kat is often over-protective of her. When Zoe announces her decision move to Spain with their uncle Harry, Kat refuses to allow her to go. She reveals that she is Zoe's mother, having been sexually abused by Harry aged thirteen. Zoe flees Walford, and Kat attempts suicide by cutting her wrists. She recovers, is romanced by local doctor Anthony Trueman, and later finds Zoe and brings her home. Their relationship improves, but after Kat breaks up with Anthony, he and Zoe begin an affair. Zoe disowns Kat for disapproving of their relationship, and later runs away when Anthony reveals that he is still in love with Kat.
Anthony and Kat's relationship resumes, but she fails to impress his colleagues and breaks up with him as he is about to propose. Kat discovers she is pregnant by him and decides to have an abortion. Her boss Alfie Moon persuades her not to, but she suffers a miscarriage shortly after telling Anthony of the pregnancy. Alfie comforts her and realises that he is in love with her. Kat soon begins a relationship with local crime kingpin Andy Hunter, and they end up getting engaged. However, Kat confesses to Alfie's grandmother Nana that she loves Alfie - who upon discovering this intervenes; he stops Kat and Andy's wedding and confesses his love for her. Kat leaves Andy, and she and Alfie marry on Christmas Day. Alfie later borrows money from Andy which he is unable to repay, so Andy threatens to kill him unless Kat has sex with him. A reluctant Kat does so, but unbeknownst to her Andy films the liaison and sends it to Alfie. Alfie becomes cold and distant and Kat resorts to alcoholism. After a one-night stand with a stranger, Roger, a disgusted Kat leaves Walford.
Several months later, Kat's grandmother Mo discovers that she is in prison for prostitution. Upon her release, Mo convinces her to return to Walford. Kat is determined to win Alfie back, but he is now in a relationship with Little Mo. Though he opts to reconcile with Kat, she is unwilling once she learns of his relationship with her sister. Kat rebuilds her relationship with Zoe, and they part on good terms when Zoe leaves to work as a holiday rep in Ibiza. Before Zoe leaves, Kat discovers that Zoe was involved in the murder of Den Watts, and tells Kat that she had been lead to believe that she had killed Den until Sam Mitchell had told her the truth about Chrissie Watts being the murderer. Kat confronts Sam about letting Zoe believe that she had killed Den and threatens Chrissie to not let Zoe's involvement become known to the police. Chrissie agrees, but in return, asks for an alibi. Kat's cousin Stacey Slater agrees to become Chrissie's alibi, but Chrissie is later caught out and arrested for Den's murder. When Nana Moon dies, Kat comforts Alfie and their feelings for one another once more become apparent. On Christmas Day 2005, they confess their love and depart Walford to travel across the United States.
Kat returns to Walford in September 2010, fleeing from a man she and Alfie conned for money. Alfie arrives but Kat is displeased to see him. She reveals to her family that while Alfie was serving time in prison, she had an affair with another man, who proves to be Alfie's cousin Michael Moon and is now pregnant with Michael's child. In an attempt to prove himself responsible, Alfie leases The Queen Victoria public house. He struggles to raise the rent, and enters into a partnership with Michael, unaware that Michael is the father of Kat's baby. After an argument with Alfie, Kat agrees to move to Spain with Michael, but ultimately changes her mind and reconciles with her husband.
Kat gives birth to Tommy, and is rushed to hospital the next day due to complications. While she and Alfie are absent, James, the newborn son of local resident Ronnie Branning, dies of sudden infant death syndrome. Ronnie swaps the babies in an act of desperation. A devastated Kat believes her father is to blame for Tommy's death, as he left him alone to go for a drink. After the funeral, Ronnie attempts to return Tommy, but Kat misunderstands and believes that she is rejecting James. Charlie opts to leave Walford, although Kat forgives him before he departs. She is shocked when Michael returns to see his son, and upset when he shows no emotion at learning that he died. Kat's friend Martina Quinn and her daughter Shenice visit from Spain. After they leave, Kat and Alfie miss Shenice, and consider IVF to try for another baby. Their consultant feels it is too soon, and their relationship breaks down again, but eventually they reconcile. Four months after taking Tommy, Ronnie returns him and hands herself in to the police. Kat reacts with disbelief, but a DNA test reveals the truth, and Kat is reunited with Tommy. Kat is initially furious with Ronnie, but forgives her when she is sentenced to three years in prison.
Kat and Alfie holiday in Spain, and bring Shenice back with them. Upon their return, Kat gets pregnant again. Alfie believes that he cannot have children and assumes Kat has cheated on him, despite her insistence to the contrary. Alfie learns that he is wrong, but Kat is hurt by his accusation and will not let him near her, even after suffering a miscarriage. Kat has a one-night stand with Mark Garland, which she instantly regrets. She eventually confesses to Alfie, and tells him that her behaviour is how she is and always will be. Alfie tells Kat he would rather have her cheat on him than not have her in his life. The couple attempt to mend relations with each other over Christmas, but Alfie overhears Kat saying that she thinks he no longer loves her. Alfie books a session with a marriage counsellor, which Kat initially refuses to attend. She turns up late, and Alfie tells her the counsellor never arrived. Alfie pays his friend Gerry (Paul Reynolds) to pretend to be a marriage counsellor, who comes to their home. Kat tells Gerry that she believes Alfie does not love her any more and so she wants to end their marriage.
After Charlie suffers a stroke, Kat stays with him for a number of months, until Roxy Mitchell calls Alfie, who is with Kat, asking him to return as Kat's relative Jean Slater has gone through many troubles involving Michael. Kat returns with Alfie and comforts Jean, who has broken down. She confronts Michael about it, but he continues with his lies, saying that Jean has been stealing things. However, Kat is not fooled and says she will rip him apart when she finds out the truth. She continues to harass Michael and his fiancée, Janine Butcher, until the police get involved and caution Kat and Jean. Alfie informs Kat that he has taken a loan from Eddie Moon but Kat later learns that Eddie is in financial difficulties and so could not have lent them money. Kat is introduced to Derek Branning, who reveals that Roxy and Alfie grew very close while she was away. Kat confronts Roxy who admits she had a crush on Alfie and confesses to giving Alfie the loan. Kat sacks her from her job as a result.
Alfie tries to start a football team for the pub, and Kat takes it over. She flirts in order to get people to sign up, and continues flirting at a party, with Derek, Michael, Ray Dixon, Jack and Max Branning, sharing a close moment with each of them. While in the kitchen alone, an unseen man enters and he and Kat have a sexual encounter. She feels guilty the next day and attempts to neglect calls and texts from the mystery man, who has bought her a new phone. Kat eventually responds and talks with the man to tell him to leave her alone, but changes her mind and they begin a frequent affair, and he supplies them with a flat to use. Kat endeavours several times to end it, but she continuously succumbs. He falls in love with her, with Kat reciprocating, and when he sends Kat flowers, Alfie becomes suspicious. Kat lies they are from Charlie, but Alfie does not believe her and asks her to be totally honest, to which Kat reveals her three-month affair, telling him he does not know the other man. Alfie is furious and throws her out. After a heart-to-heart with Michael, Kat returns to The Queen Vic to ask for Alfie's forgiveness and suggests going away for a while.
Alfie forces her to end her romance, which Kat does, and they go away together to try and salvage their marriage. When they return, they are shocked to be sacked by Phil Mitchell. However, Kat convinces Phil to give them their jobs and home back, by telling him she is trying to repair their relationship after the affair. When her mystery lover gives her another key to their flat, she writes "Kat loves Alfie" in lipstick on a mirror. As time goes on, Alfie becomes steadily more paranoid of Kat's activity, believing she is still having the affair. Alfie follows her the bedsit where there are petals on the bed and candles are lit. She refuses to answer his questions but Alfie finds a letter address to Mr Branning. Alfie goes back to The Queen Vic where he confronts all three Branning brothers. One of their phones rings, and Alfie answers Kat's call. The phone is Max's, but Kat reveals that it is Derek she was having the affair with. Alfie kicks Kat out of their home and Kat stays with Derek, who promises to show Alfie a message on her phone where she tries to break up with him, but he plays a message where she begs to see him. Kat discovers this and an argument between them, along with Derek's other family arguments, lead to him dying from a heart attack.
Alfie starts a relationship with Roxy, who moves in with Alfie, upsetting Kat. Kat teams up with Bianca Butcher (Patsy Palmer) to earn money cleaning, first at the R&R and then at The Queen Vic after being given a job by Roxy. Kat and Bianca are fired from both jobs, so they decide to set up a market stall together, with Alfie offering money to help them start. Kat is upset when Alfie changes the licensee name from Kat to Roxy on the plaque above The Queen Vic doors. Alfie helps Kat when she is questioned over stolen goods, but to prove his love to Roxy, he decides he wants to divorce Kat. Kat fights with Roxy, and has sex with Michael, which she regrets the next day, Lauren Branning tells Kat to take control of her life, so Kat tells Roxy and Alfie she had sex with Michael and that he is a better lover than Alfie. Kat has an ongoing feud with Roxy, and is upset when she finds out Roxy and Alfie are trying for a baby. When a man named Josef tries to steal money from the pub's safe, Kat helps Roxy by convincing him not to. Roxy thanks Kat but then accuses her of trying to win Alfie back, which Kat denies. Kat and Alfie receive their decree nisi. Kat says it is not too late to cancel, but Alfie insists he has moved on and proposes to Roxy.
When Kat learns that Roxy is not going to meet Ronnie at her release from prison, she goes instead. Ronnie is unwilling to talk to Kat at first, but soon the pair discover that various tragedies in their past mean that they have plenty in common. Kat offers Ronnie a bed for the night, and then gradually persuades Alfie to accept Ronnie's presence back in Walford. This and Michael's death bring Kat and Alfie closer together. The night before his wedding, Alfie visits Kat and it leads to them kissing passionately, but she stops it. Distraught that she cannot be with Alfie, Kat decides to leave Walford, but Bianca takes her to the wedding and Kat walks in to see Alfie say "I do" to Roxy. She leaves the church and heads for the airport, but after she has boarded the plane, Alfie embarks and declares his love for her. He is forced off by security and Kat follows, reuniting with a kiss.
Phil decides to sell The Queen Vic, as revenge for Alfie's treatment of Roxy, and Kat and Alfie move back in with Mo. Kat then reveals that she is pregnant by Alfie, and discovers that she is having twins. Having spotted her cousin Stacey Branning from the top deck of a bus, Kat decides to track her down. She visits Janine in prison, and agrees to provide a false witness statement for Michael's murder, in return for Janine dropping false charges against Stacey, so that she can return to Walford. At her trial, Janine confesses to her crimes, and Kat is charged with perjury. She is devastated when Stacey hands herself over to the police for Archie Mitchell's murder, five years previously. Kat attends a hearing, and is given a suspended sentence. After the market is merged with Spring Lane, Kat immediately clashes with her new rival, Donna Yates and is later surprised when Alfie reveals he has bought a pitch on the market. Kat gives birth to Bert and Ernie Moon. Stacey is released after she appeals her sentence and comes to live with Alfie and Kat. The financial situation becomes worse for the Moons when Alfie reveals they are to be evicted as they have not been paying their bills.
Kat briefly works the market again, but marker inspector Aleks Shirovs forces her off her stall when he discovers she is working and claiming maternity benefit. Alfie lies to her that he has managed to convince the council to give them more time to rally together the money they need, but secretly plans to claim house insurance by setting fire to their house. He does so, but is unaware Kat is inside. She becomes trapped although Alfie rescues her. She is badly burnt and suffers permanent scarring to her face. On leaving hospital, she and Alfie remarry with two nurses as the only witnesses, before returning to the square and moving into a flat Alfie has organised for them to squat in. When the owners arrive, they are thrown out and Kat is angry with Alfie, although out of desperation they squat in a new flat with help from Donna. Lee Carter calls the landlord of the flat when trying to fix the boiler, so they are evicted again and they stay at The Queen Vic with Alfie's friend Mick Carter. After Kat makes an emotional speech to the social housing manager, they are offered a council house in Hull. Stacey tries to stop her but before they leave Kat discovers a photo of Nana that was not lost in the house. Alfie confesses that it was he who started the fire. Kat, appalled by the disclosure, insists their marriage is over and stays with Stacey and Lily. Mo tells Kat that Harry left her some money in his will. Alfie finds out, and tries to convince her to use the money to make a fresh start after the divorce. She takes the cheque from Mo and later rips it up in front of Alfie, insisting it doesn't change the past nor their impending divorce.
Kat begins to have second thoughts about the divorce after Pam Coker gives a speech about love and family. Stacey reveals to Alfie that their rent is increasing and Kat is struggling with money. Alfie then invites Kat to his flat for lunch and they reminisce about their relationship. The next day, Kat lashes out at Alfie for leaving leftovers for the children, but at the urging of Stacey, she agrees to be his date to Ian and Jane's wedding if he makes more effort for making up for the fire. On the wedding day, she gets heavily drunk, and during the reception, shoves Sonia Fowler's (Natalie Cassidy) head into the wedding cake. When the nursery raise their rates, Kat is forced to leave the children in Mo's care to work her shift at the market, but ends up having drinks with Kim Fox-Hubbard. When Mo brings the children over to the pub, they misbehave and Kat is thrown out of the pub. Undeterred, Kat and Kim continue drinking and sneak into the pub to steal another bottle of wine. Linda Carter, catches them, and while Kim leaves to find the cash to pay for it, Linda prepares to call social services to tell them of Kat's irresponsibility as a mother, but Kat snatches Linda's phone and throws it across the ground. When Kim returns with Shirley Carter, she confesses her fears about being a bad mother, resulting in the other three women sharing their experiences of motherhood and reassuring her. Kat also tells Linda to speak to Mick about her fears that the baby may not be his. Linda then realises that the phone call was still connected, and promises to fix things to make sure social services do not know about what happened, however Kat receives a call from a social worker requesting to visit her. Kat is surprised when a lawyer visits her about Harry telling her about a compensation case with four other women also raped by Harry.
After the visit from the social worker, Kat tells Stacey and Mo that she will start saving up to visit Zoe in Spain. Two days later, Kat receives a text from Zoe saying she does not want to see her. Kat is devastated and she writes a letter to the solicitors about receiving all the remaining money from Harry's will, and intends to post it the next morning. The next day, following a conversation with Shabnam Masood, Kat changes her mind and throws the letter away but Mo retrieves it and posts it on her behalf. After Kat is robbed, Stacey discovers that Kat has been overdosing on Tommy's medicine. Kat admits to drinking the medicine to numb out her thoughts about Harry, but promises to stop. When Stacey tells Mo that the money would not be good for Kat, Mo has a change of heart and has Harry's money transferred to her own account. Kat later finds out about this, and then, after burning the money, falls into a depression and tries to kill herself. Alfie finds her and calls an ambulance, at the hospital he admits that he is still in love with her. He takes her home and decides to stay temporarily in order to help her with the children and her upcoming visit from another social worker. During the visit, Kat remains withdrawn from answering questions about how she is feeling and why she attempted suicide and insists she is fine, but Alfie says on her behalf that she is not fine but that they are working on it, and admits to the social worker his feelings of guilt from starting the fire.
After she almost kisses Alfie, Kat nearly has sex with Max, but regrets it and goes to Alfie for comfort. The next day, she tells Alfie that she wants to get back together with him, but he tells her that he is not ready as he does not want to hurt her again. This causes Kat to reevaluate her life, so she visits the convent where she gave birth to Zoe to seek some answers, though it is now a nun's care home. A nun, Sister Ruth, remembers her going into labour and they talk about the past and the future. Kat then leaves and goes to the police station to make a statement about Harry. Ruth checks their records and discovers that Kat also gave birth to a son. Later, a content Kat returns to Walford and tells Stacey and Alfie that she has finally made her peace with the past and is no longer willing to let Harry control her.
Kat tells Alfie that she wants to reunite with him, and although he initially resists, he later changes his mind. They buy a lottery scratchcard and win £1,000,000. They then plan to move to Spain so Kat can be closer to Zoe. Alfie discovers he has a brain tumor and decides not to tell Kat, so as not to worry her. Kat and Alfie then leave with Tommy, Bert and Ernie to live in Spain.
Kat returns to Walford to spend Christmas with Stacey. Alfie follows with the children, and it is revealed that Zoe does not want to see her. Kat is surprised when Sister Ruth visits her, and reveals the truth about her son, whom the nuns called Luke, and Ruth reveals he was adopted by an Irish family. Kat realises Mo knew about Luke, and argues with Mo and Charlie. Charlie has a heart attack and dies, leaving Kat devastated. Belinda returns and blames Kat for Charlie's death. Alfie tells her that he has a brain tumour, but assures her it is benign. Kat vows to attend Charlie's funeral, despite her sisters not wanting her there, but on the day, Stacey is mentally ill so Kat stays with her at The Queen Vic. She makes amends with Belinda and tells her about Luke. Belinda then reveals that Viv once took the family (minus Kat) to a village in Ireland called Redwater, and Viv visited a church and left crying, blaming Kat for this, and Belinda saw a couple with a boy watching them leave. Kat then finds out information about Redwater but she and Alfie then leave for Spain.
Kat & Alfie: Redwater and EastEnders: The Podcast
In episode 1 of Kat & Alfie: Redwater, Kat (referred to as "Kathleen" in the series), Alfie and Tommy arrive in the Irish town of Redwater, where Kathleen is almost immediately convinced that Andrew Kelly (Peter Campion) is her son, while Andrew's grandmother, Agnes Byrne (Fionnula Flanagan) is suspicious of her. Alfie warns Kathleen to wait for the right time and make friends first, but Kathleen confides in Agnes's husband Lance (Ian McElhinney) that her son was taken away from her in 1983 and she believes he is in Redwater. Lance tells Agnes this, and Agnes immediately says Kat should not be told the truth as it would unravel everything they have built. Kathleen visits the Byrnes' farm and talks to Andrew about his life, but then Lance warns him to give the Moons a wide berth. Kathleen then admits to Alfie that she is scared of seeing how disappointed her son would be in her. Lance tells the local priest, Dermott Dolan (Oisín Stack), that Kathleen is his real mother. It is revealed that Iris Dolan (Orla Hannon) lost a baby in London and brought Dermott back as her own, and her husband Peter (Stanley Townsend) does not know the truth. The next day, Dermott murders Lance by drowning him.
In episode 2, Kathleen and Alfie are invited to Lance's wake by Peter, and when speaking to Agnes and Lance's daughter, Eileen Harrington (Angeline Ball), Kathleen realises that Andrew cannot be her son. Agnes confronts Kathleen and Alfie, so Kathleen realises that Lance told her why they are there. Agnes says Kathleen gave up her right to see her son when she gave him up, but Kathleen explains she did not know she had a son as she had passed out during the birth. Dermott and Tommy hear this, and Tommy asks if he has a big brother. Later, Kathleen and Alfie decide to return to Spain, but Tommy wants to find his brother. Tommy sneaks out of the house, and Kathleen and Alfie try to find him. Andrew's mother, Roisín Kelly (Maria Doyle Kennedy), tells Kathleen that she saw Tommy at the church, so they go there, followed by Agnes. They find Dermott praying with Tommy, who tells Kathleen that he found his brother. Kathleen realises that Dermott is her son, and Dermott confirms this.
In episode 3, Kathleen and Dermott have bonded, but she lies to him about who his real father is. Dermott worries that Tommy will tell Peter the truth and threatens him. Alfie realises that Kathleen lied to Dermott, which results in an argument. Dermott overhears them arguing about him not knowing the truth and Kathleen refusing to tell him. In episode 4, Agnes urges Kathleen to return to Spain. When Dermott learns of this he confronts Agnes about taking him from his mother. In episode 5, Agnes tells Dermott to keep Kathleen away from the christening of Bernie Kelly's (Susan Ateh) baby, but Dermott says Kathleen has made him feel welcome and invited him to meet his brothers in Spain, so Agnes reveals that Dermott has a twin sister. Dermott confronts Kathleen over this, who said she was waiting for the right time and insists there is nothing else that Dermott does not know.
In episode 6, Bernie, a local garda, asks Kathleen about the last time she saw Lance and Kathleen wonders if she suspects something happened, but Bernie denies this. Meanwhile, Kathleen is unaware that Alfie is having an operation on his brain tumour. Alfie asks Dermott to find Kathleen and bring her to the hospital, as it means they are unable to go back to Spain. Bernie works out that Dermott was involved in Lance's death, and sees him on the beach with Kathleen. Kathleen tells Dermott that Bernie was asking about him. He sees the garda arriving so takes Kathleen in a boat, saying they will try to find the whale that was recently seen off the coast. Bernie shouts at him to stop and calls the coastguard. Kathleen asks Dermott if he did something to Lance. Dermott then accidentally crashes the boat into a rock and Kathleen is thrown into the water and cut by the propellor. Dermott gets Kathleen out of the sea but there is nobody around to help. Meanwhile, Alfie has his operation but loses his pulse and the medical staff start to resuscitate.
In episode 1 of EastEnders: The Podcast, "Kat's Indecent Proposal", set in Málaga in March 2018 and released in November 2018, Kat and Alfie have been running a bar in Spain but have split up and Kat is in a relationship with their business partner, Dimitri (Andrew Byron), who proposes to Kat. Kat finds out from Sofia (Gloria Sanders) that Dimitri invested in Kat and Alfie's bar so that he could run it into the ground and eliminate his competition. Kat wants to see the contract Alfie and Dimitri signed, which makes Alfie think she wants a divorce and he decides to close down the bar. Kat realises Dimitri's controlling ways and decides to take Tommy, Bert and Ernie back to England with Alfie, and leaves Alfie a voicemail saying this and telling him that she loves him. However, Alfie deletes the voicemail without listening to it. Kat and Dimitri go to the bar but Alfie is out, so they stay the night. The next morning, Dimitri does not allow Kat to leave the bed to make breakfast for the children. Tommy decides to make breakfast and Kat's relative, Hayley Slater (Katie Jarvis) arrives to witness Tommy dropping the kettle on Ernie, who is scalded. Kat sees this and screams.
Mo returns to Walford, telling Stacey that Kat has died. Stacey raises money for Kat's funeral, but Jean arrives and tells Stacey that Kat is not dead as she spoke to her that day; Mo has lied to raise money as she has financial problems. Kat returns to Walford and is confused that The Queen Vic is holding a benefit night for her and confronts Mo, but hides when Ian brings the raised money. After Ian leaves, Kat reveals that she and Alfie are taking a break from their marriage and he is in Spain with their children running a bar with a Russian partner after their old bar lost a fortune. Kat, Stacey and Mo arrive at The Queen Vic when Mick is giving a speech about Kat and attempt to maintain that Mo made a mistake, but she starts a fight with Karen Taylor (Lorraine Stanley), which starts a bar fight. Jean pays off Mo's debt, and Kat starts a cleaning business to pay Jean back. Kat is furious when she finds Hayley in Walford. She demands that Hayley leave, but Hayley threatens to reveal what has happened in Spain. It becomes clear to the Slaters that Kat is hiding something and it is revealed that Kat has had an affair and was not watching when one of the children burnt themselves, leading to Alfie kicking her out. Kat does not know that soon after this incident, Alfie and Hayley had a one-night stand, which has resulted in Hayley becoming pregnant with his child. After Hayley tells Alfie, who is staying in London, about the pregnancy, he tries to persuade Hayley to terminate the pregnancy and returns to Spain, but Hayley decides to keep the baby.
Kat gets a video call from Alfie and he asks her to collect something for him. Believing him to still be in Spain, she follows his instructions and goes to a chapel where she is surprised to see Alfie in person. Alfie is running a funeral business and has many clients lined up, but Kat is unimpressed and only sees it as a scam. She is angry that he has not brought their children with him, but apologies for cheating on him with Dimitri. Kat tells him to stop his lies and jokes and she leaves. The following week Kat speaks to Alfie, who is back in Spain, by video call and she is angry when he says he lied to her and actually did bring the children with him to London. Two weeks later, during Hayley's birthday party, Kat answers the door and is shocked to see Alfie standing on the doorstep. Though he reunites with Kat, he is stunned to realise that Hayley did not terminate her pregnancy, and insists they keep the truth hidden from Kat. Hayley develops feelings for him when she sees him bond with their daughter, named Cherry by Alfie after his deceased mother. Jean, who is the only one who has found out about Alfie being Cherry's father, insists that Alfie tell Kat or she will.
When Kat goes out on her motorbike, she visits a café that Charlie used to take her to when she was a child. Kat meets family friend Tony, who remembers her and Charlie and they bond over their memories. Tony takes Kat to his local pub, where they see Tony and Charlie's friend, Maurice, but he is reluctant to meet Kat. When Kat demands to know Maurice's problem with her, he tells her that one night he was with Charlie and her uncle Harry, and Harry said he "knew how to shut her up". Maurice realised that he was talking about sexually abusing Kat and hoped it was not true, but could not tell Kat if Charlie had heard this or not. This causes Kat to become uncertain of who she can trust for several days. Alfie brings Maurice to Walford see Kat, and Maurice admits that Charlie did not hear what Harry said and apologises, saying he was drunk when he told Kat, and admits he never really liked Charlie and saw the lie as a way of getting back at Charlie but did not think how it would affect Kat, so he apologises. This comes as a great relief to Kat, who tells Alfie she can trust again.
Stacey sees Hayley and Alfie kissing and is horrified to uncover Cherry's paternity and issues an ultimatum: one of them leaves, or Kat learns the truth. Hayley decides to go, but her parting gift to Alfie – a lock of Cherry's hair – is discovered by Kat and she works out the truth. Horrified about this and that Jean knew, she furiously trashes the living room and smashes the windows in Alfie's car, then after a tearful drunken karaoke performance at the pub, realises that Stacey also knew and admits she can no longer trust anyone after what happened. After she yells at him, Alfie turns nasty with Kat, who accuses him of taking advantage of Hayley's vulnerability. Hayley defends Kat and pushes Alfie, causing him to fall down the stairs and knock himself unconscious. Believing that he is dead, Hayley, Kat and Stacey discuss what to do to protect Hayley from going to prison. Kat privately says a tender goodbye to Alfie, kissing him and telling him she loves him. As the police arrive, they discover that Alfie survived and has left, taking Cherry with him. The next day, Kat leaves a voicemail on Alfie's phone, pleading with him to bring Cherry back. Alfie eventually contacts Kat and Hayley via video chat and says he will bring Cherry back soon. On New Year's Day, Alfie and Kat meet and Kat tries to talk him into returning Cherry but Alfie admits he cannot bring himself to do it, fearing he would only be granted limited visitation time, and suggests he and Kat adopt Cherry and leave together. Conflicted, Kat at first decides to accept and asks Alfie to come to the empty house through the back door. However, she later changes her mind and tells Stacey, Mo and Jean, who proceed to confront Alfie when he arrives. Angry and upset, he shows them Ernie's scars caused by Kat's irresponsibility. When Kat takes the children for ice cream, she gives Alfie the option to take them with him on the condition that he brings Cherry back to Hayley. Alfie eventually relents to return Cherry and leave their children with Kat, admitting that he loves her and only wanted her to be happy. The next day, after emotionally attempting to say goodbye to Cherry, Alfie changes his mind and attempts to drive out of Walford with her but finds himself stuck in traffic. This forces him to reevaluate his decision and he turns back and returns Cherry to Hayley. When Ian tells Kat that Hayley rejected Alfie's offer to be a part of Cherry's life, a sympathetic Kat allows him to spend time with their children. Kat reconsiders a relationship with Alfie, but Alfie's scam leads into debt and after borrowing money from Phil Mitchell (Steve McFadden) and not being able to pay it back, Alfie flees Walford and fakes his death, leaving Kat with money which he took from Phil.
Phil taunts Kat for the money that Alfie had stolen from him, but Kat does not know about the money or on Alfie's whereabouts and Phil holds her responsible for Alfie's debt to him. However, Kat later discovers the money and uses half of it to fund for Jean's cancer treatment. Things come to a head when Phil takes Tommy and asks him questions about Alfie. After a brief fling with Kush Kazemi (Davood Ghadami), they begin dating, but their relationship is under threat when Kush announces that he wants to file for joint custody over his and Stacey's son, Arthur. Stacey accuses Kat of supporting Kush and a rift forms between them. Kat attempts to rebuild their relationship but a hurt Stacey refuses and kicks Kat out of her home. Kat moves in with Kush and makes several attempts to reconcile with Stacey which backfires in her face when Stacey hides the money that Alfie had left her. Unfortunately for Kat, Phil revives his interest on the money and he asks Shirley Carter (Linda Henry) to retrieve the money back from the Slaters. They eventually give the money back but Phil continues to menace the Slaters about keeping the money. Whilst drunk in the Queen Vic, Kat drunkly mocks Phil about the stolen money and as a result Phil threatens her children. This leads to a showdown between Kat and Phil in the Archers. Martin tries to intervene but Phil becomes aggressive with him and Stacey, in defense, hits him across the head with a wrench. Phil's son Ben Mitchell (Max Bowden) arrives soon after and orders the Slaters to leave. Stacey and Martin flee Walford in fear of Stacey being imprisoned. Ben frames Keanu Taylor (Danny Walters) for the attack and he also flees Walford. Kat reveals the truth about the attack to Kush and he moves into the Slater household to support her against Phil. After recovering, Phil starts to remember details about the attack and confronts Kat who reveals that Ben had covered it up. As revenge, Ben threatens Kat about Stacey being the culprit.