In addition to her TV and movie credits, Guilbert had made a name for herself in theater. She starred in the 2005 Broadway play, A Naked Girl on the Appian Way, as well as The Matchmaker, Arsenic and Old Lace, Waiting for Godot, Harvey and To Kill a Mockingbird.
On Wednesday morning, Guilbert's Nanny co-star, Fran Drescher paid tribute to her onscreen grandmother with a series of tweets. "I feel so sad about Annie. She was brilliant as my Grandma Yetta. Such a sweet woman too," Drescher wrote and posted along with photos of Guilbert from the '90s sitcom. "Such a great actress! I thank you Annie. Thank you for all the laughs! May you be cracking them up in heaven!"