Robin Williams' Daughter Zelda Shares Heartwarming Family Photo on Late Actor's Birthday

Robin Williams' onscreen daughter, Sarah Michelle Gellar, also paid tribute to the comedian.

Zelda Williams paid tribute to her famous father, Robin Williams, on what would be his 65th birthday.

The 26-year-old actress shared a throwback photo on Thursday of her dad playfully hugging her, along with his two sons, Cody and Zach. Zelda captioned the sweet pic with a promise to the late comedian.

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"Still not really sure what to do on days like today," Zelda wrote. "I know I can't give you a present anymore, but I guess that means I'll just have to keep giving them in your name instead."

She then pledged to make a donation in her dad's honor to "Thought you'd get a kick out of furry, four legged friends helping change the world, one warrior in need at a time," she continued. "Happy birthday Poppo. Shasha, Zakky, Codeman and I all love you and miss you like crazy. Xo"

Meanwhile, Sarah Michelle Gellar, who played Williams' onscreen daughter on the CBS sitcom The Crazy Ones, also remembered the late actor on social media. Gellar posted a photo of behind the scenes with her former co-star to Instagram, and quoted Thornton Wilder, writing: "There is a land of the living and a land of the dead and the bridge is love, the only survival, the only meaning."

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She added, "I will always think of you Robin with love, love and more love. #happybirthday #robinwilliams"

On Twitter, Gellar quoted Williams and shared a collage of her time on The Crazy Ones with him. "'No matter what people tell you, words and ideas can change the world' -RW Happy Birthday Robin," she wrote.

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Zelda has now landed a TV role of her own on Dead of Summer, and shared with ET in June, the hilarious advice she received from her father. "He always said, 'Don't wear your mic pack to the bathroom,'" she quipped. "'Don't do that, ever. If you're mic'd don't go anywhere or say anything that you don't want other people to hear because there's probably, like, 30 people with headsets on listening.'"

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