Robin Williams' tragic suicide could have been triggered by Lewy Body Dementia, sources connected with his family have confirmed. The celebrity gossip site TMZ obtained documents showing that the late actor was struggling with the disease, which disrupts normal human functions with abnormal protein deposits on the brain.

Robin WilliamsRobin Williams [L] in The Fisher King, for which he won his third Oscar nomination

The lewy body form of dementia is commonly associated with Parkinson's and sufferers are said to get severe side effects from Parkinson's medication. Hallucinations are said to be one of the most common side effects, with patients seeing phantom objects, people or animals. According to TMZ, the patients often try to communicate and interact with the illusions, though it is not clear whether Williams experienced this.

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However, his wife had told authorities shortly after his death Robin had been complaining about certain medication and the way it made him feel. Sources connected with the family said Lewy Body Dementia was the "key factor" in Williams' suicide and doctors are believed to agree that the disease was a "critical factor" in his suicide.

Meanwhile, the Daily Mail reports that Williams left a $50 million estate to his three children, Zachary, Zelda and Cody. The Oscar-winner set up a trust fund dated January 31, 2011, which was filed three months after his death.

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The actor also made sure his third wife Susan Schneider would be taken care of, in a prenuptial agreement they signed before their 2011 wedding. 

Williams, who struggled with depression, bipolar disorder and drug and alcohol addiction throughout his long and illustrious career, committed suicide at his San Francisco home on August 11. He was 63-years-old. 

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