EXCLUSIVE: Cher gives update on 91-year-old mother's health: 'She's fabulous'

Cher is happy to report that her mother, Georgia Holt, is doing "really great."

"You know, my mom is 91 and she's fabulous," the 70-year-old icon told ET's Carly Steel at Thursday's premiere of The Promise in Los Angeles. "She has some rough moments but for all [intents and] purposes, she barely takes any medication."

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"She has to worry about just a few things, about getting pneumonia," she continued. "That's the thing I worry about the most."

See photos of Cher and Georgia Holt together:

Last month, the "Turn Back Time" singer worried fans when she dropped out of a Lifetime movie due to a "serious family issue." A source told ET at the time that Cher's inability to commit to the film stemmed from her concern for her mother's "fragile" state.

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"Cher's worried about her mother's health. She's in her 90's now and does not want to be far from her," the source told ET in March. "Her mother is not deathly ill, but is somewhat fragile. "

The source also added, "Cher's health is fine."

See photos from "The Promise" premiere: