RELATED: See Robin Williams’ Three Kids Now. Zachary, who goes by Zak, posted a lengthy tribute to his father on Twitter. “Dad, seven years ago today, you passed on. The joy and inspiration you brought to the world carries on in your legacy and in your family, friends, and fans you so loved,” Zak wrote. “You lived to bring laughter and to help others. I will be celebrating your memory today. Love you forever.” The message was shared alongside a photo of Robin with long tousled hair and a full beard. RELATED: See Jack Nicholson’s Daughter Lorraine, Who’s an Actor and Filmmaker. While Zak’s post for his father was sweet and sentimental, some people took offense. In a since-deleted tweet—captured by Entertainment Tonight—a Twitter user wrote, “I support Zak, and I miss his dad. But [Robin Williams] didn’t just ‘pass on.’” The user noted that Williams died by suicide, adding, “If we can’t name the things for what they are, how can we expect to help anyone in [the] future?” Zelda came to her brother’s defense and responded to the critic. “How about we let people who’ve lost loved ones mourn and verbalize their loss how they feel comfortable?” Zelda wrote. “He’s my brother, and his son, and a father in his own right. We’re people too, not just advocates. Please don’t forget that on this often dehumanizing app. Have compassion.” Zelda tweeted a message of support and solidarity for anyone who has experienced loss themselves on the anniversary of her father’s death. “Sending love out there today to all the folks navigating loss. New, old, the connective tissue of that deeply human pain can be hard to bear,” Zelda wrote. “But I find it easier sometimes knowing how many others have felt the same sting. We’re not alone. X.“ae0fcc31ae342fd3a1346ebb1f342fcb RELATED: For more celeb news delivered straight to your inbox, sign up for our daily newsletter. Zelda and Zak have been active mental health advocates since their father’s death. Two years after his passing, Robin’s wife at the time of his death, Susan Schneider, penned an essay in Neurology about her husband’s health struggle and the challenges they faced when trying to find the proper diagnosis for him. “My husband was trapped in the twisted architecture of his neurons, and no matter what I did, I could not pull him out,” Schneider wrote. Although Robin was diagnosed with Parkinson’s disease a few months before his death, Schneider said, “somehow I knew Robin was not buying” the diagnosis. Robin’s autopsy revealed that he had Lewy body dementia (LBD) rather than Parkinson’s. “The massive proliferation of Lewy bodies throughout his brain had done so much damage to neurons and neurotransmitters that in effect, you could say he had chemical warfare in his brain,” Schneider explained. “I have since learned that people with LBD who are highly intelligent may appear to be okay for longer initially, but then, it is as though the dam suddenly breaks, and they cannot hold it back anymore.” RELATED: This Was the First Sign of Parkinson’s That Michael J. Fox Noticed.