A cause of death was not immediately provided.
"I wanted to bring in as much humanity as possible, as well as the humor", Rae told The Associated Press early in the show's run.
Rae's representative confirmed the news Sunday, saying she died surrounded by family and friends at her Los Angeles home.
"The Facts of Life" debuted in 1979 and centered around Mrs. Garrett's relationship with a group of girls she met in the season 1 finale of "Diff'rent Strokes". I've had a wonderful one already... Rae also earned an Emmy nomination for her role in the 1975 special Queen of the Stardust Ballroom. "No, no, no! If people had a positive experience with Mrs. Garrett, that makes me so happy!" She said the "most devastating thing" she faced was her son Andy Strauss' diagnosis of autism at a time when there was far less understanding of or attention to the disorder.
Randy Moss absolutely crushed his Hall of Fame speech
He thanked every team he played for, including the Wilf family for re-opening the doors for Moss back in Minnesota. You promised the state a stadium, and y'all delivered. "And a Super Bowl will be coming your way".
In her April 2017 statement, Rae also said, "At 91, every day is a birthday".
Stage work was a passion for Rae, who in NY had appeared in a landmark production of Kurt Weill's "Threepenny Opera" and as Mammy Yokum in the hit musical "L'il Abner". She was Tony-nominated in 1966 for her work in the musical "Pickwick" and in 1969 for the play "Morning, Noon, and Night". She later did local theater, but broke into television as Sylvia Schnauser, the wife of Al Lewis' Officer Leo Schnauser on the classic comedy vehicle 54, Where Are You?
Todd Bridges, who famously played young Willis Jackson along Rae's Mrs. Garrett on Diff'rent Strokes, paid tribute to all of his late costars: "RIP IN PEACE ALL OF MY CAST MATES". Her ex-husband, composer John Strauss, died in 2011 after a battle with Parkinson's.
She is survived by her sister, Miriam Guten, and her son, Larry.