Robin Williams would have just recently turned 70 years old if he were still with us today, and his children are remembering their father as son Zak shed some new light on the legendary comedian's final days. In 2014, Robin Williams died by suicide at the age of 63, news that came as a tremendous shock as he always seemed to be so full of life. His death has since been attributed to his struggles with Lewy body disease which had severely affected his brain by the time of his passing.

In a recent interview on The Genius Life podcast with host Max Lugavere, Zak Williams spoke about the frustration his father felt leading up to his death. Initially, Robin was diagnosed with Parkinson's disease and wasn't properly treated for his Lewy body dementia. Zak explained that the drugs his father was taking for Parkinson's were "really hard on the mind and body," and that Robin only grew more depressed when he noticed his condition affecting his work. Robin's eldest son theorizes that this may have "exacerbated the situation."

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"What I found was someone who was having challenges performing his craft. And that was really irritating for him. Because when you're a performer, it goes beyond taking pride in performing. It's your livelihood, and suddenly that becomes challenging," Zak explained about the struggles of Robin Williams in his final days. "I mean, beyond empathy I couldn't help but feel frustrated for him because the neurodegenerative thing - it's rough."

Zak added: "The thing though is, there was a diagnosis and the like but when he died by suicide, it had progressed, but he was only maybe two years in. So I don't wanna say it was a short period, it felt a lot longer than it actually was, but it was a period for him of I think intense searching and frustration... There was just more anxiety and depression and just things he was experiencing and talking to me about that made me realize that he was - it was very uncomfortable."

Because his father's struggles were apparent, Zak says he reached out to him more consistently in Robin's final days. "I mean we talked several times a week, but then it got to the point where you're talking every day," Zak also said. "I wanted to be there for him on a daily basis. I really wanted to because it can be really isolating, even if you're with family and loved ones."

On Robin Williams' 70th birthday, Zak posted to Instagram: "Dad, on what would be your 70th birthday, I would want you to know that your incredible spirit lives within us. Our family will be celebrating you and your memory today. We miss you and love you always!"

In another post on Twitter, Zak's sister Zelda also thanked Robin's fans for the kind words sent her way. The post reads: "Thanks to everyone who sent thoughtful things on Poppo's bday. Celebrated him in my own way yesterday, grateful for the space to do so. It's gotten a little less strange over the years, and I've gotten a bit less scared of being me in the face of it. All things in time I guess..."

After Robin's passing, Zak admits he struggled with his own mental health issues and was later diagnosed with PTSD. He has since become a passionate mental health advocate and works with organizations like Bring Change 2 Mind to help develop mental health support communities in high schools throughout the United States. This news comes to us from The Hollywood Reporter, and you can listen to the full interview with Zak on The Genius Life podcast.