Robin Williams, famous for his impeccable sense of humor and giving us movies like Aladdin, Mrs. Doubtfire, Jumanji, Dead Poets Society, and so many others, seemed to spread joy wherever he went.

However, on August 11th, 2014, the Academy Award-winning comedic actor died by suicide following a general decline in his mental health.

Well, today on July 21st would have marked the actor's seventieth birthday, and his son Zachary has opened up about how he still feels the gaping hole in his life from his father's premature death.

Yesterday, Zak shared a message on Instagram as a tribute to Robin on his birthday, 7 years after his death. Zak, now thirty-eight-years-old expressed in his caption: "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!"

Before his death, Robin had been incorrectly diagnosed with Parkinson's disease. It wasn't until after his tragic death that an autopsy revealed the Good Will Hunting actor had actually had Lewy body Dementia - one of the most common types of dementia. Lewy bodies develop in nerve cells in the brain regions involved in thinking, memory, and movement.

On the July 21st episode of The Genius Life podcast, per People, Zak opened up about the frustrations his father faced surrounding his final years:

"What he was going through didn't match one to one [with what] many Parkinson's patient's experience. So, I think that was hard for him."

Zak continued, explaining how his father struggled with focusing and was "very uncomfortable."

"There were issues associated with how he felt, and also from a neurological perspective he didn't feel great."

He also revealed that the medications his father was taking were "really hard on the mind and the body." He expressed what he felt for Robin was "beyond empathy" and the son was "frustrated."

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He continued: "It can be really isolating even when you're with family and loved ones." There were only 2 years between Robin getting his diagnosis and his death, with Zak stating that time period "felt a lot longer than it actually was because it was a period for him of intense searching and frustration."

Following his death, Zak said he was diagnosed with Post Traumatic Stress Disorder and turned to alcohol to cope with the grief. He shared that he underwent a twelve-step program for addiction recovery, as well as group therapy. Zak is now the CEO of Prepare Your Mind, a wellness and anxiety-alleviating product he worked on after his father's death. He is also a mental health advocate.

Rest in Peace, Robin... and happy birthday.