Mo Harris

Mo Porter-Harris was born in 1936, the eldest child of an impoverished family in the East End of London.

She departed EastEnders in 2016, with Kat & Jean, leaving Stacey as the only Slater left.

In 2017, it was confirmed Kat Slater, Jean Slater & Mo would be returning to the show as part of a storyline branching from Kat and husband Alfie Moon's apparent deaths on Redwater.

Storylines
At the age of 14 she becomes pregnant following a one-night stand with Stuart Mullins, a ticket collector for the Waltzer ride at a fairground in South London, and gives birth to their daughter Vivienne the following year in 1951.

Best friends with Pat Harris, Mo falls for Pat's older brother Jimmy and after a whirlwind romance they marry in 1959 and go on to have two children of their own: Billy and Jean. However, Pat threatens to disrupt their marriage due to her alcoholism and eventual prostitution, which diverts Jimmy's attention away from Mo and onto Pat; this results in Mo beginning an affair with Pat's pimp Tony Cattani in 1963. When Pat discovers them together she informs her brother but Mo denies Pat's accusations and as a result Jimmy disowns Pat and they move away to Lewisham. Jimmy later dies of cancer in 1979. His final wish is to make amends with his sister Pat but instead Mo neglects to inform her of both his death and his funeral.

Mo Slater returns to Walford after almost forty years away along with her Son-in-law Charlie Slater and granddaughters Lynne, Kat, Little Mo and Zoe. Mo's rivalry with Pat arises again, but they reconcile at Jimmy's grave on the twenty-fifth anniversary of his death.

Birth Times for Tommy & Zoe

Mo receives a phone call from Kat who wants Zoe's birth certificate. Mo meets Kat at a café, and gives her the certificate. Kat reveals to Mo that she conned a man, and now needs a new identity. Kat also lies to Mo, and says that her husband Alfie Moon is dead. Mo persuades Kat to come home to see her family, and Kat reluctantly accepts but when they both get home, men are waiting for Kat and her money. Alfie turns up at the Slater house and chases the men away. Mo is then shocked to learn that Kat is pregnant, and Alfie is not the father. When Kat goes into labour, Mo delivers her son, Tommy, on the floor of The Queen Victoria's barrel store.

On the same day, Ronnie Mitchell gives birth. On New Year's Eve, Ronnie's baby dies of cot death and she secretly swaps the babies. Alfie and the rest of the family then discover the dead baby, believing it to be Tommy.

In April Mo stole Flowers from Ian Beale a t Lucy's Coffin and wishes Kat Good Luck in her court how will Ian react when he sees mo doing the wrong thing and will she get arrested

2018 return
On the 20th December 2017, it was announced that Mo, portrayed by Laila Morse (Big Fat Gypsy Gangster, The Ninth Cloud) would be returning to EastEnders, along with fellow Slater ladies Kat and Jean, after moving to Kent to live with her granddaughter Belinda Peacock. No details have been released on upcoming storylines. Laila said of her return: "I’m really excited to be coming back. It’s the one question I’m constantly asked. I can’t wait to see everyone and get stuck back into life in Walford!", whilst EastEnders executive consultant said "The Slaters are one of the all-time great families in EastEnders and Albert Square has never felt quite the same since they scattered to different ends of the country, and in some cases beyond."