Oscar-winning actress Diane Keaton, known for her roles in films like “Annie Hall” and “Something’s Gotta Give,” died on Saturday at the age of 79 . According to those close to her, the death was unexpected.

A friend told PEOPLE that Keaton’s health had declined rapidly.

“She declined very suddenly, which was heartbreaking for everyone who loved her,” the friend said. “It was so unexpected, especially for someone with such strength and spirit.”

According to the source, Keaton spent her final months surrounded by close family, who kept her condition private.

No official cause of death has been released.

Months before her death, Keaton listed her cherished Los Angeles home for $29 million in March. She spent eight years renovating the five-bedroom, seven-bathroom estate, a process

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