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Brad Paisley and Kelly Clarkson are among the many celebrities using Twitter to express their sadness over the death of Robin Williams

[Get The Story: Robin Williams Dead of Apparent Suicide]

And they both use the same word to describe their feelings.  Paisley tweets, "Devastated right now. Loved you Robin," while Clarkson says it was "devastating finding out about @robinwilliams."  She adds that he was "an amazing talent and incredibly sweet. So sad." 

[PHOTOS: Remembering Robin Williams]

Both Paisley and Clarkson shared the screen with Williams on his last TV series, "The Crazy Ones." 

Kelly was featured on the series premiere last September.  At the time she said Williams had been one of her favorite stars since she was a kid, and she was thrilled to work with him. 

Brad was a guest star along with Josh Groban on an episode that aired in April. 

Williams was found dead at his home in Tiburon, California Monday.  He was 63. 

PHOTOS: Remembering Robin Williams