The 28-year-old beauty is set to play the female lead in Ted 2, the follow-up to Seth MacFarlane's raunchy 2012 comedy, Deadline reports.
Mark Wahlberg is set to reprise his role in the film while Mila Kunis will reportedly only have a small part, if any. The Black Swan beauty portrayed Wahlberg's girlfriend Lori in the original film, which centered on a boy who couldn't cut ties with his teddy bear that came to life as a result of a childhood wish.
Lori (Kunis) and Wahlberg's character John Bennett wed at the end of the first film, which went on to become the highest grossing R-rated movie of the year. Seyfried's character and storyline in the sequel currently remains unknown.
So why the casting change?
Deadline reports Kunis and MacFarlane remain close, and the switch-up is nothing more than a creative decision made by MacFarlane as he will once again produce, write and costar in the upcoming sequel. Mila will reportedly still provide the voice of Meg in the producer's hit show Family Guy.
This isn't the first time that Seyfried and MacFarlane have worked together. The Les Miz actress stars in the American Dad creator's most recent film, A Million Ways to Die.
As for Kunis? She most recently completed filming The Angriest Man in Brooklyn opposite Peter Dinklage, Robin Williams and Melissa Leo.
Ted 2 is slated for release on June 26, 2014.
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