Hunter Parrish will play her son and Alec Baldwin will take on the role of her husband.
Kristen has had a quiet few months as she has focused on her burgeoning fashion career.
She was named as the new face of Chanel late in 2013 before jetting to the brand’s Metiers D'Art Paris-Dallas show in Dallas, watching the show from the front row and wearing the Chanel Spring 2014 collection.
Kristen Stewart and Julianne Moore on set of Still Alice
Last week the actress was rumoured to be in talks with Nike as their new front woman, thanks to her love of their trainers which she is often spotted wearing on the red carpet.
Four time Oscar nominee Julianne has also signed on to star alongside Jennifer Lawrence in The Hunger Games: Mockingjay Part and Two, which are slated for release in November 2014 and 2015 respectively.