California nimal rescue, Helen Woodward Animal Center, honored the late Diane Keaton on Tuesday, Oct. 14, for her service as a board member and her work on animal welfare

The cause of death of Oscar-winning actress Diane Keaton has reportedly been revealed. Keaton, 79, died on Oct. 11 of pneumonia, according to People magazine, which cited a statement from the actress' family, which also expressed thanks for "the extraordinary messages of love and support."

While it wasn't clear whether Keaton had any underlying conditions, doctors say "perfectly healthy" people can die from pneumonia.

Diane Keaton spent several months in Palm Springs and surrounding desert cities prior to her death. One desert attraction was clearly her favorite.

Keaton’s death has broken hearts across Hollywood as friends, colleagues and fans try to grapple with it. Here’s what we know so far about how she’ll be honored.

The Oscar winner died at 79 on Oct. 11. NBC News medical contributor Dr. Natalie Azar shares why she was at a higher risk for severe effects of pneumonia.

Diane Keaton's death certificate has been released days after she died in Santa Monica at 79 years old on Oct. 11.

Richard Gere is paying tribute to legendary actress Diane Keaton.

Elizabeth Berkley is looking back at her time with Diane Keaton. The actress, 53, starred in the “First Wives Club” alongside the late Hollywood vet, who died at age 79 on Oct. 11. The star-studded cast also included Goldie Hawn, Bette Midler, Sarah Jessica Parker and Maggie Smith.