Shelley Morrison (Rosario) will not return to the show because she retired from acting.
Her last on-screen role was in My Name is Earl.
Last acting credit was voice work for an animated film, Foodfight!
Don't expect Rosario to stay in the show like Karen's husband, Stan, was: invisible. "We're dealing with her as a character and we're writing to it very specifically," W&G co-creator Max Mutchnick said.
As for Bobbi Adler... The writers plan to address Grace's mother's absence on the show.
The only other confirmed returning guest star is Harry Connick, Jr., who played Grace's husband, Leo.
ONTD, who do you want to return on WAG?