Two of Robin Williams' three children, Zelda and Zachary, marked what would have been their late father's 75th birthday with heartfelt public tributes on social media. The comedian died by suicide in August 2014 at age 63, following a struggle with severe depression and undiagnosed Lewy body dementia.

Zelda Williams, 34, shared a touching message on her Instagram story, reflecting on her father's enduring spirit. "Happy 75th womb evacuation anniversary Poppo!" she wrote, using a familiar nickname. "Not sure what 75 would've looked like on you. Probably the same loud socks and cool jackets. Maybe some more crazy glasses as your eyesight got worse. Grayer, but no less hairy." She added, "Wish we could talk about the world and joke about my haunted pups. Bet your laugh would be the same. You are loved beyond measure and missed daily. Happy 75th Poppo."

Alongside her message, Zelda posted a photo strip from a photo booth, showing her and her father laughing together. Zelda, who is set to voice the Chaos Terran character Spitfire in the animated series Transformers: EarthSpark in 2024, is the elder of Williams' two children with his second wife, Marsha Garces Williams. They also had a son, Cody, who passed away in 2022.

Zachary Williams, 43, also paid tribute to his father on Instagram, sharing a picture of the comedian in his iconic alien character from the ABC sitcom Mork & Mindy. "Happy 75th Dad!" Zachary wrote. "Today I'm remembering your weirdness and your extraordinary capacity to love. I remember those wrinkles in the corners of your eyes - the kind you get from a lifetime of smiling. I remember your unending need to see this world free of human and animal suffering."

Zachary and his wife, Olivia June, co-founded Prepare Your Mind, a company offering amino acid supplements formulated for stress resilience, inspired by Williams' own desire to alleviate suffering. Zachary is Williams' eldest son, from his first marriage to Valerie Velardi.

The anniversary of Williams' death, August 11, approaches, marking 12 years since his passing. The actor, known for his diverse roles in films such as Dead Poets Society, Hook, Aladdin, Mrs. Doubtfire, Jumanji, The Birdcage, Good Will Hunting, and the Night at the Museum series, had been misdiagnosed with Parkinson's disease months before his death.

His struggles with Lewy body dementia were the subject of the 2020 documentary Robin's Wish and the 2018 HBO documentary Robin Williams: Come Inside My Mind. Williams, a graduate of the Juilliard School, was one Tony Award away from achieving EGOT status.