The iconic Walford matriarch will be killed off in the coming weeks, after Peggy returns to the Square to say her final goodbyes to her family.
Fans saw her reveal her terminal cancer diagnosis in a shock episode of the BBC soap earlier this year, after Barbara made the decision to leave the character behind once and for all.
Speaking about filming her last ever episode, she told The Mirror that the cast and crew had "done her proud".
"'EastEnders' did me proud, I couldn’t have asked for more. They gave me great directors, great writers, and the people I love are performing with me. It’s sad but perfect. Everyone at 'EastEnders' has worked really hard to give Peggy a fitting send-off and I’ll never forget that."
In the weeks before her death, Peggy will be reunited with sons Phil (Steve McFadden) and Grant (Ross Kemp), the latter of which is returning to the soap especially for the storyline.
"I think of them as very, very dear friends. I’ve been very blessed to have had both Steve and Ross as my on-screen sons as they are both great actors. I couldn’t have come back and filmed my final scenes without us all together."
Danniella Westbrook has also confirmed she will be returning as Peggy's daughter Sam for a handful of episodes.
Barbara, who was made a Dame in the Queen's New Year's Honours List, announced her departure from 'EastEnders' in January, explaining she felt it was the right time to “shut the door” on the character.
She said at the time: “Everyone knows I love ‘EastEnders’ and that will never change. Peggy is a character close to my heart but I made the decision a while ago that I need to say goodbye to Peggy once and for all as otherwise she will always be there, urging me to go back and that is something I need to shut the door on.
“After thinking long and hard about it, I realised that it is time for me and the audience to say our final farewells to the lady who I have loved for many years and I thought that whilst the guvnor [executive producer Dominic Treadwell-Collins], who I adore, is still in charge, I want him to be the one to oversee it."
Peggy's return to Walford airs on Monday 9 May at 8pm on BBC One.
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