Robin Williams was diagnosed with Parkinson's disease shortly before his death, his wife Susan Schneider has revealed. A preliminary investigation conducted earlier this week determined that the 63-year-old actor died on Monday, Aug. 11 from asphyxia by hanging.

Schneider added that the Academy Award winner hadn't publicly disclosed his diagnosis before his probable suicide. He had been candid about his struggles in the past, including an uphill battle with sobriety.

In a statement released Thursday, Aug. 14, Schneider said (via NY Daily News), "Robin’s sobriety was intact and he was brave as he struggled with his own battles of depression (and) anxiety as well as early stages of Parkinson’s disease, which he was not yet ready to share publicly.

"His greatest legacy, besides his three children, is the joy and happiness he offered to others, particularly those fighting personal battles." She continued, "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."

On Tuesday, Williams' three children, Zak, Zelda and Cody released heartfelt statements mourning the loss of their father and celebrating his life. Sadly, harassment of Zelda, 25, began on Twitter shortly after, and the actor's only daughter announced she was leaving the social media network following disturbing tweets.

The tweets included photoshopped photos of her father with bruises around his neck. The Washington Post reported that the two Twitter accounts behind the majority of the abuse have since been suspended.

Watch a Tribute to Robin Williams

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