Diane Keaton’s health deteriorated rapidly in recent months ahead of her death.

A friend of the actress told People that “she declined very suddenly, which was heartbreaking for everyone who loved her.”

According to the friend, her rapid decline was “unexpected.”

Keaton and her loved ones also chose to keep her health battle private.

“In her final months, she was surrounded only by her closest family, who chose to keep things very private,” the source said. “Even longtime friends weren’t fully aware of what was happening.”

But there was one alarming signal in March — she listed her “dream home” in Los Angeles for $29 million, which surprised her friends given that she had previously said she planned to remain there permanently, People reported.

A source also told the outlet that Keaton was known for walking her dog daily in her Brentwood neighborhood, but was not seen for the past couple of months.

“She loved her neighborhood,” the source said. “Up until just a few months ago, she’d walk her dog every day. She was usually dressed the same, with a hat and her signature sunglasses regardless of the weather.”

“She was always very nice, funny and chatty,” the source continued. “She’d talk to her dog like he was a person. She was eccentric and had this old-school Hollywood aura. She was very, very special.” 

Keaton died in California, a family spokesperson told the outlet Saturday. No cause of death was given.

She’s mourned by her two children, daughter Dexter and son Duke, both of whom she adopted in her ’50s.

The Oscar-winning actress looked healthy and happy in her last Instagram post, which she shared in April. Keaton shared adorable pics with her dog, Reggie, and is pictured smiling big.

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