Dana Daly

July 21 marked what would have been Robin Williams's 73rd birthday, and in honor of the bittersweet occasion, his son, Zachary Pym "Zak" Williams, took to social media to share a heartfelt tribute. In his message of remembrance, Zak reflected fondly on "the hope and joy" his famous father brought to countless people the world over. Comedy legend Robin Williams was 63 when he died after a long battle with anxiety, depression, and mounting paranoia. His autopsy found "diffuse Lewy body disease," and his symptoms were consistent with Lewy body dementia. Since his father's passing, Zak, 41, has worked in mental health advocacy, and his a co-founder and CEO at Prepare Your Mind (PYM), whose mission is "to provide safe, natural and effective mental hygiene products to promote self-care and end the stigma around mental health." Here is how he is continuing to honor his father's memory and legacy of joy amidst the pain. Zak Williams honors Robin on his 73rd heavenly birthday https://twitter.com/zakwilliams/status/1815029902791557232 On July 21, Zak took to social media to share a tribute to Robin Williams just in time for the Mrs. Doubtfire star's 73rd heavenly birthday. "Dad, on what would be your 73rd birthday, I remember you for all the hope and joy you brought to the world," he captioned his post. RELATED: Zelda Williams Shares Hilarious Candid Photos Of Her Late Father, Robin Williams Zak continued, "There's not a week that goes by without someone sharing with me how you helped them through a dark time or a rough patch. I'm so grateful to be your son. Love you forever." His post is accompanied by a black-and-white photo of Williams sitting with his legs crossed in a meditative pose, fingers carefully folded and resting on his knees. As he has been seen so often in the past, in the photo, Williams appears to be smiling as he rests in front of a couch laden with various props. Devotion to a worthy cause Zak Williams mourned and celebrated his father Robin on his 73rd heavenly birthday / Instagram Zak, born in 1983, is Williams's son with Valerie Velardi. The two met in '76, back when he was working as a bartender at a San Francisco tavern, just two years before he secured national attention thanks to ABC's Mork & Mindy, which ran from 1978 to 1982. Williams and Velardi separated in 1988. He is half-brother to Zelda, born in 1989 and named after the famous Nintendo series, The Legend of Zelda; she is the daughter of Marsha Garces, who Williams was with from '89 to 2010. They also had son Cody Alan Williams, born in 2008. Throughout his private mental health battles, Williams always took great pride in his children, each of whom he was "so proud of them in different ways," he told the Today show in 2009, adding in his characteristic way, "Have they always been cherubs? No, but that’s been part of the process." Williams suffered from depression / © Sony Pictures / courtesy Everett Collection Just as Williams harbored pride in each of them, they each honor his legacy in their own ways, with Zak devoted to mental health awareness. "I never set out to be an advocate," he told Forbes, "but it just so happened I found that service was very healing for my trauma." He went on to explain, "Through my healing journey, I discovered that learning about the systems and interventions relating to mental health support became part of a deeper mission around finding ways to better be of service to causes relating to mental health. The way in which I celebrate my dad’s legacy is trying to be a good dad, trying to be kind and considerate when and where possible, and figuring out opportunities to best be of service." In fact, Zak was there when policymakers were rolling out the new 988 Suicide & Crisis Lifeline, working with experts to understand the various updated features the new rollout would introduce and implement in the long term. He even worked with podcast network Lemonada Media on a four-part special outlining the service to provide transparency and normalcy to a valuable resource. He also launched the startup PYM, which he calls a mental hygiene company whose policy and products are all about helping others build the support system Zak used during his own battle with depression after his famous father's passing. https://twitter.com/zeldawilliams/status/1682497867511128064 When honoring her father for his birthday last year, Zelda put a spotlight on Robin's own devotion to the arts and supporting those fighting for their due in the workplace. "Happy birthday to Poppo, who definitely would’ve been out there fighting the good fight for art and artists today and always," she said in her own tribute post. At the same time, she also has a history of remaining transparent about the pain such occasions still bring to her and her family. "Everyone who has dealt with loss knows the pain of certain anniversaries, moments full of memory that come round like clockwork and usurp all others," she penned, "no matter how hard you may try to prepare for or avoid them." She continually promotes togetherness as a vital part of having a reliable support system, emphasizing, "Being together was the important thing, because otherwise, especially with people scattered to the wind with work, it became even more special to do that." A poignant 73rd heavenly birthday to Robin Williams. Zelda / Xavier Collin/Image Press Agency RELATED: Robin Williams’ Daughter Zelda Honored Her Late Father On His Birthday By Giving Back