Diane Keaton’s co-star honors following her death

Diane Keaton’s death has shocked fans and Hollywood colleagues, with her co-stars mourning and paying tribute.

Oscar-winning actress The First Wives Club co-star Bette Midler spoke out about her passing in an Instagram post on Saturday, October 11.

"The brilliant, beautiful, extraordinary Diane Keaton has died," Midler wrote, alongside a black-and-white photo of her former co-star and longtime friend, posing in a suit and hat.

"I cannot tell you how unbearably sad this makes me," the Hocus Pocus star added. "She was hilarious, a complete original, and completely without guile, or any of the competitiveness one would have expected from such a star. What you saw was who she was…oh, la, lala!"

Midler described Keaton as a "brilliant, beautiful [and] extraordinary" actress.

Keaton’s Father of the Bride co-star Kimberly Williams-Paisley also paid tribute after hearing of her death.

“This breaks my heart. Getting to work with Diane Keaton will always be one of the highlights of my life,” Kimberly wrote in the comments section of PEOPLE's Instagram post announcing the actress’s death on Saturday.

On October 11, news emerged that Keaton had passed away at the age of 79. A family spokesperson told PEOPLE that she was in California, and no further details about her death are currently available. Her family has also requested privacy as they grieve her loss.

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