Robin Williams was suffering from Parkinson's disease, his wife revealed on Thursday.
Susan Schneider released a statement addressing rumours that Williams had relapsed from drug and alcohol sobriety – sharing that her husband was suffering from a different kind of disease.
"Robin's sobriety was intact and he was brave as he struggled with his own battles of depression, anxiety as well as early stages of Parkinson's disease, which he was not yet ready to share publicly," she said.
"It is our hope in the wake of Robin's tragic passing, that others will find the strength to seek the care and support they need to treat whatever battles they are facing so they may feel less afraid."
Williams was found lifeless in a bedroom at his San Francisco-area home on Monday at around noon. Officials reported that the death was a suicide by hanging.
The Oscar-winning actor and comedian battled with substance abuse and mental health issues for decades, and a representative for Williams said Monday that he had been dealing with "severe depression of late." It is unclear when Williams was diagnosed with Parkinson's disease.
The nerve system disease affects bodily movements, and becomes progressively worse over time.
In the early stages, people with Parkinson's may suffer from hand tremors, speech slurring, and impaired balance, according to the Mayo Clinic. The disease can also cause problems with cognition, sleeping, and digestion. The cause of Parkinson's is unknown, and there is no cure. Other famous personalities with Parkinson's disease include actor Michael J. Fox, and retired boxer Muhammad Ali.
Schneider, Williams' third wife, asked for privacy in a statement the day her husband's death was announced.
"This morning, I lost my husband and my best friend, while the world lost one of its most beloved artists and beautiful human beings," she wrote. "I am utterly heartbroken. On behalf of Robin's family we are asking for privacy during our time of profound grief. As he is remembered, it is our hope the focus will not be on Robin's death, but on the countless moments of joy and laughter he gave to millions."
Williams had three children from prior marriages.