Libby, daughter of Denise Fox (Diane Parish), will return to Walford later this summer for two episodes.
She'll make her return to Albert Square to celebrate her birthday with her family, but producers tease: "Is there more to her visit than she is letting on?"
Speaking ahead of her return, Belinda said: "It's great to be back again! I'm always excited to see how Libby has grown and be back with the Fox family!"
Libby was last seen in Walford in May 2014 for Lucy Beale's funeral. She originally left Albert Square in August 2010 to study at Oxford University.
In other EastEnders news, Dean Gaffney will also reprise his role as Robbie Jackson later this year. As one of Albert Square's most memorable characters, viewers will see Robbie back for a short stint.
Dean has since hinted that producers are thinking of ways of how Robbie's beloved dog Wellard could return to the show.
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