Deadline is reporting that producer Judy Craymer is confident that a third Mamma Mia! film will come to fruition. In the interview, Craymer, the force behind the stage musical and its subsequent two films, mentioned that Sabrina Carpenter would portray a "goddess or some relation who would look very much like Meryl Streep." I'm not exactly sure what that means, but it makes me think that Carpenter would be playing a younger version of Meryl or her granddaughter perhaps? I can actually see the resemblance in the photo below.
Craymer flat out confirmed that Meryl would be in the third film, "nodding affirmatively" when asked, and adding "Yeah, she (Meryl) said our after-shooting dinners were legendary. There is a script, but I'm not going there." Craymer also suggested the possibility of a Mamma Mia! television series in the future.
I could of course take it or leave it if Meryl involved herself in this project. But I do like the idea of her being involved in another film that does well at the box office, especially if she has more than a cameo like she did in the sequel. That, combined with the Devil Wears Prada sequel could be a nice boon to her career, which only helps in green-lighting future projects in which Meryl might wish to participate.
Keep 'em comin', Meryl!