Former Holby City and This Life actress Luisa Bradshaw-White has been cast in the role of Tina, who will make her first appearance on screen in November.
Tina is Shirley's younger sister and viewers will soon discover that there are a lot of similarities between the siblings.
Billed as "loud, brash, cheeky and full of energy", nothing about Tina fades into the background and she is bound to get up to no good on the Square.
Tina's arrival could lead Shirley (Linda Henry) astray and show chiefs have promised that there are big plans for the feisty siblings.
Speaking of her new role, Bradshaw-White commented: "I am so excited to be joining EastEnders to play Tina as she is such a brilliant character to play. Linda is an amazing person to work with and the energy between Shirley and Tina is explosive!"
The casting of Tina comes as EastEnders' new executive producer Dominic Treadwell-Collins continues to make his mark on the BBC soap. Since taking office last month, he has already brought in comedian Terry Alderton to play a new love interest for Bianca Butcher.
An EastEnders insider told Digital Spy: "Luisa is Dominic's second signing since he returned to EastEnders, and seeing as Dominic was the mastermind behind creating Shirley, there are bound to be really big things in store for Tina.
"Luisa is a great signing for the show. She's a fantastic actress and along with Linda Henry, the Carter sisters are really going to shake things up. There is a real buzz at Elstree at the moment as Dominic is starting to put his plans into place and everyone is really excited about the next few months."
Bradshaw-White has already begun filming ahead of her debut later in the year.
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