While no cause of death was immediately available, in 2017 Rae had discussed being diagnosed with bone and pancreatic cancer.
The actress played Mrs. Garrett on the beloved 1980s series, a spin-off of Diff'rent Strokes.
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The Tony and Emmy nominated actress appeared on the popular 1980s sitcom "The Facts of Life" for almost 10 years, sharing her personal struggles with the writers for the show to keep things realistic.
"So now, at the age of 91, I have to make up my mind".
According to TMZ, Rae also appeared in "The Love Boat", "101 Dalmatians: The Series", "Sesame Street", "Car 54, Where Are You?". I'm not in any pain right now.
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One aspect of parenting that has surprised her is she is acting just like her mother, Kris Jenner, did when she was a baby. The 15th season of KUWTK premieres this Sunday night on E! at 9 p.m.
Born Charlotte Rae Lubotsky, she was best known for her role as beloved housemother Edna Garrett, who first appeared on "Diff'rent Strokes" in 1978 before earning her own spinoff, "The Facts of Life", the following year. "I'm feeling so terrific and so glad to be above ground", Rae told People Magazine.
Charlotte Rae said it was a "miracle" they found the pancreatic cancer "because usually, it's too late".
"I had lovely wigs", Rae said. Now I have to figure out whether I want to go have treatment again or opt for life. Rae left the show in 1986 for health reasons, and though Cloris Leachman stepped in as Mrs. Garrett's sister, the show was canceled two years later.
Rae is survived by her sister, Miriam Guten as well as her son Larry, whom she shared with ex-husband John Strauss.