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Born July 21, 1951, to a former model and a Ford Motor Company executive, Chicago native Robin Williams began his showbiz career inside his own home, where he'd make his mother laugh by doing impressions of his grandmother, according to the AP.
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BEST IN CLASS
By the '70s, he took that talent to New York City's prestigious Juilliard School. There, he befriended classmate Christopher Reeve (here with Williams at the 1979 People's Choice Awards). "I'd sit back and hope to catch the girls that were downstream," he later joked to PEOPLE.
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Reaching for the stars took a literal turn when Williams portrayed Mork, an alien from Planet Ork, on Happy Days in 1978. His extraterrestrial performance earned him and costar Pam Dawber an ABC spin-off called Mork & Mindy, which ran from 1978 to 1982.
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Four months into his marriage to Valerie Velardi, a modern dance teacher, Williams found sudden fame in sitcom TV. The couple had one child together, Zachary, in 1983, before divorcing in 1988.
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While starring on the TV hit, Williams developed a cocaine habit. "Most people get hyper on coke. It slowed me down," he later told PEOPLE in 1988. "It made me withdrawn. And I was crazy back then – working all day, partying all night. I needed an excuse not to talk." But the death of Saturday Night Live's John Belushi helped scare Williams sober in 1982 – he had spent hours with Belushi before the comic overdosed on heroin and cocaine.
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Williams took his act to the road on multiple stand-up tours, including An Evening with Robin Williams (1982) and Robin Williams: At the Met. He also brought the laughs for a good cause: Beginning in 1986, he teamed up with Whoopi Goldberg and Billy Crystal for the Comic Relief special, a star-studded HBO telethon benefiting the homeless. "There were no cell phones when we started. There were just phones in the old days," he joked to PEOPLE when the special returned in 2006 after a hiatus.
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A CHANGE OF HEART
"Right now I'm moving through my personal life like a hemophiliac in a razor factory," Williams said in 1988 amid marital struggles. The comedian found himself torn between wife Valerie and Marsha Garces, the couple's 20-something live-in nanny for son Zachary. They married in 1989 and had two children (Zelda Rae and Cody Alan) before divorcing in 2008 after 19 years of marriage.
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Williams's career took a serious turn in 1987 when he portrayed convention-defying Armed Forces Radio Service deejay Adrian Cronauer in the war comedy Good Morning, Vietnam. The performance earned him an Academy Award nomination for Best Actor, as well as a Golden Globe Award.
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WORDS TO LIVE BY
"No matter what anybody tells you, words and ideas can change the world," Williams stated in 1989's Dead Poets Society, a drama marked by his nuanced portrayal of an English teacher who dares to think outside the classroom. His performance as John Keating earned him another Oscar nod, as well as a Golden Globe nomination.
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NO DOUBT ABOUT IT
Layers of prosthetics and a shiny gray wig turned Mrs. Doubtfire into a 1993 hit and transformed the actor into America's favorite nanny. In April 2014, it was reported that a sequel to the family classic is in development at Fox 2000.
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The father of three (Zachary, Zelda and Cody) credited his children for helping him commit to sobriety. "If I had a choice to erase from my life something, I would leave all the memories of my children," he said in 2006, "even the memories when they misbehave because it is still extraordinary."
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BIRD IS THE WORD
Three years after Mrs. Doubtfire, Williams once again helped bring drag to the big screen in 1996's dazzling The Birdcage, a remake of the 1978 La Cage aux Folles. Contrasting his performance with costar Nathan Lane's, PEOPLE's critic pointed out his layered performance, writing, "Williams, on the other hand, is unusually sensitive. He lets a lot of bruised hurt seep through the comic froth."
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Williams took an unusual turn for the dramatic, playing Matt Damon's therapist in 1997's Good Will Hunting, and Hollywood noticed, rewarding him with an Oscar. "It's the same sense I had on Dead Poets Society, that there was something really powerful there," he told Boston magazine in 2013. "I just knew it was a really beautiful piece of writing that's worth doing, getting it out there. That alone, you gotta say, 'I gotta take the shot.'"
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The actor received the 2005 Cecil B. DeMille award at the Golden Globes, cracking up the crowd with impressions during his acceptance speech. But he also got serious for just a second, thanking the Hollywood Foreign Press for recognizing comedy and thanking his wife Marsha and three children for standing by him throughout his career.
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After 20 years of sobriety, Williams re-entered rehab in August 2006, seeking treatment for alcohol abuse. That October, he spoke to Good Morning America about his addiction. "There's a voice and it's a little quiet voice that goes, 'Jump,'" he explained. "That same voice that goes, 'Just one.' And the idea of just one for someone who has no tolerance for it, that's not the possibility."
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Following his role in 2009's Night at the Museum: Battle of the Smithsonian, Williams embarked on a well-received stand-up tour and, in 2011, made his Broadway debut in the drama Bengal Tiger at the Baghdad Zoo. "With Robin, we see all that work happening right before our eyes, in a much faster way than I think is humanly possible," the play's writer, Rajiv Joseph, told New York magazine.
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THIRD TIME'S THE CHARM
Williams married his third wife, Susan Schneider, in Napa Valley, California, in October 2011. The two met before the actor underwent heart surgery in 2009, and Schneider, a graphic designer, reportedly helped nurse the star back to health following his procedure.
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A SAD GOODBYE
On the evening of Aug. 11, 2014, news broke that the actor died of an apparent suicide at age 63. He'd checked back into rehab in July to "fine-tune and focus on his continued commitment," according to his rep, but as Williams told Good Morning America in 2006, addiction never ends. "It's just there," he said. "It lays in wait for the time when you think, 'It's fine now, I'm OK.' Then, the next thing you know, it's not OK."
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