Ava Hartman made her first appearance 20 November 2012. She is portrayed by Clare Perkins.
In July 2012, Cora tells Tanya that her daughter, Ava Anderton, was born in 1964 but was taken away by the staff while Cora was sleeping and they told her that Ava had died. In fact, Cora was forced to put Ava up for adoption.In November, Cora tells her partner Patrick Trueman that Ava is alive and Patrick tells Tanya. Tanya tracks Ava down, and discovers she in the deputy headmistress of a local school. Tanya and Patrick visit the school, where Tanya is shocked to see Ava is mixed-race and tells her she is moving to the area. Ava gives them a tour of the school but Tanya runs out, leaving her purse behind. Tanya agrees to say nothing to Cora and not see Ava again and she and Patrick drive away before Ava can return the purse. Ava returns the purse the next day and Cora invites Ava in. Cora is shocked when Ava reveals her name. Ava learns the truth, and has a long talk with Cora, telling her she had thought about finding her before but decided the past was best left in the past, and nothing has changed, so leaves. A few weeks later, Cora visits Ava and gives her a bracelet that was given to Cora by Ava's father, along with a Christmas card. Ava later brings Cora a card in return, and wears the bracelet. Later, Tanya's daughter Abi Branning befriends Dexter Hartman, and invites him to dinner with her family. Ava gatecrashes and berates Tanya for meddling. Tanya is clueless, and it is then revealed that Dexter is Ava's son. Ava is angry with Dexter for not speaking to her about what he was doing. Ava then gets a job at a school in Walford.
Ava helps out when Bianca Butcher's son, Liam, is involved with a gang that Dexter used to be a member of. They gang trash Ava and Dexter's home, and they move to Albert Square. Ava does not want to have anything to do with Cora, but Dexter urges her to, and she starts a friendship with Billy Mitchell, who has a romantic interest in her. Their date is interrupted by Ava's ex-husband and Dexter's father, Sam James. Ava resents him because he claimed to have gone out to buy milk but did not return for 20 years, and both Ava and Dexter want Sam to leave. However, Ava slowly realises she still has romantic feelings for Sam and they have sex. The pair reunite and Dexter slowly warms to his father. It emerges that Sam requires a kidney transplant. Ava hopes to donate one of hers but is not a match. Dexter decides to take a test to see if he is a match, but Ava refuses to let him. He does so anyway, and he is a match, and Dexter and Sam go through the transplant operation. Ava fusses over both of them while they are recovering, and while Dexter is used to Ava's overprotective nature, Sam feels smothered. On Dexter's birthday, Ava discovers that Sam only came to Walford to get Dexter's kidney, leaving her furious. She throws him out, but keeps the reason for his departure secret from a devastated Dexter. Blaming her for Sam's sudden disappearance, Dexter moves in with Cora. Ava is offered a job in Newcastle, and Cora urges her to take it, but she turns it down. Dexter then discovers the truth about why Sam left. He emails the company offering the job, pretending to be Ava, and accepts the job on her behalf. She then agrees to go, but decides Dexter should stay in Walford because he has his own life now. Ava then thanks Cora, calling her "mum", and leaves.