Actress Tiana Benjamin, 21, is to join EastEnders to play Chelsea Fox.
Chelsea is the daughter of Denise Fox, who will be played by Diane Parish.
Denise quickly becomes romantically involved with Kevin Wicks, played by Phil Daniels, and Chelsea will be central to their storylines.
Kevin's son Deano, played by Matt Di Angelo, has already arrived in the Square.
Desperate to be liked, he has told Pat that her nephew Kevin has died, leaving him an orphan. Pat takes Deano in and is shocked when Kevin turns up out of the blue weeks later, with sister Carly, played by Kellie Shirley.
Tiana said: "I've been a big fan of EastEnders since I was little and I'm very excited to join the show. I've always really admired Diane and I can't wait to work with her - it really hasn't sunk in yet!"
Tiana will be in EastEnders from May 2006.
She is currently starring in the Harry Potter film The Goblet of Fire, in which she plays a character called Angelina Johnson, the captain of the Quiddich team for Gryffindor House.