The world was stunned to hear that Robin Williams, the beloved entertainer who took his life on Monday, was in the early stages of Parkinson's Disease. His wife Susan Schneider released a personal statement with the shocking news, and while Williams was "not ready to share publicly," he would not have been alone in his battle.
Several of the biggest names in Hollywood have long battled the disease. Michael J. Fox famously revealed in 1998 that he had been diagnosed with early onset Parkinson's, seven years earlier at the age of 30.
The actor tweeted that he too was "stunned" by the revelation that Williams had the disease.
Fox has been a huge activist for the disease since his diagnosis. The Michael J Fox Foundation, which he founded in 2000, has been committed to the campaign for increased Parkinson's research.
ET was with Fox back in 1999 when he spoke before Congress to help raise more awareness.
"What we we're really looking to do is get folks and Congress to obviously focus on the idea that we're not just representing our situation but bring attention to the fact that this is doable," he told ET.
Muhammad Ali was diagnosed back in 1984 and like Fox has maintained a healthy life since his diagnosis.
Other celebs such as Johnny Cash, Casey Kasem and Golden Girls star Estelle Getty all suffered from Parkinson's in the late years of their lives. Robin's Hook costar Bob Hoskins was also diagnosed with Parkinson's. He died of pneumonia this year.
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