Tonight's episode sees Tanya (Jo Joyner) remain in shock after discovering a birth certificate revealing the existence of a sister she never knew she had.
Although Cora (Ann Mitchell) is still furious with Tanya for snooping through her personal belongings, she provides an explanation by disclosing that Ava died just after being born.
Tanya is sympathetic towards her mother, but still cannot believe that she kept this a secret for so many years. As Cora loses patience with her questions, she can't resist giving Tanya some harsh home truths about all the times she has lied and cheated herself…
EastEnders airs tonight at 8pm on BBC Two.
> 'EastEnders' Cora has young fanbase, says Ann Mitchell
> Read our spoiler for tonight's 'EastEnders' episode
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