The son of Robin Williams is speaking out.

A podcast interview with Zak Williams, 38, features his thoughts on the psychological challenges of his father.

Podcaster Max Lugavere hosts “The Genius Life” every Wednesday.

They spoke candidly about their struggles with anxiety, depression, and the pain of witnessing a loved one succumb to a debilitating neurodegenerative disorder: dementia with Lewy body. Williams and Lugavere have both witnessed a parent suffering from the “frustrating illness” — the pain has had a lasting effect on both of them.

“What I saw was frustration,” Zak said about his father’s diagnosis and misdiagnosis.

Two years ago, Williams was killed by suicide. Doctors told him that he had Parkinson’s disease.

The disease would have an impact on his central nervous system and cause movement problems.

An autopsy revealed that Robin and his medical team had wrongly treated the illness.

Zak said, “What he was going through didn’t match one to one [with] many Parkinson’s patients’ experiences.”

Zak says his father’s misdiagnosis likely exacerbated the emotional toll that dementia takes on patients. His son observed his struggles to focus as well as the “challenges performing his craft.”

Williams experienced anxiety and depression prior to his death.

“It was a period for him of intense searching and frustration,” Williams said. “It’s just devastating.”