Laura Norton has been cast as wayward Kerry Wyatt, who was heartbroken when Amy (Chelsea Halfpenny) was first taken into foster care.
Show bosses have confirmed that Amy will bump into her mother while out celebrating her 18th birthday in an upcoming episode.
As Amy flirts with a handsome man in a nightclub on her big day, she has no idea that he is her mum's boyfriend - but all becomes clear as she suddenly comes face-to-face with Kerry.
Kerry makes the most of her reunion with Amy and arrives in the village the next day to look for her, hoping to build bridges once and for all. Viewers will then see Kerry fight to get back into Amy's life.
Norton commented: "I am delighted to have been given this role. Emmerdale has always been my favourite soap and it's a joy and privilege to be joining the team. Kerry is an amazing and unpredictable, appealing character and I will have a lot of fun getting to grips with her.
"I have met up with Chelsea who plays Amy and I can't wait to play her reckless mum."
Emmerdale's series producer Stuart Blackburn added: "Laura is a fantastic actor and it's a delight to welcome her to the show. Her character Kerry is sure to liven things up for Amy, Val, Eric and everyone who crosses her path."
Norton's previous screen credits include roles in Vera, Steel River Blues and Angel Cake.
The actress begins filming in June and her first Emmerdale episode airs in mid-July.