Rihanna celebrated her 20th birthday at Les Deux in Hollywood, with Kanye West, actor Wilmer Valderrama and her maybe-boyfriend Chris Brown. The party included a cupcake fight and a special a capella version of "Happy Birthday" sung by Brown.
Rihanna and Brown are currently denying a relationship, but a party guest says the two were cuddling and acting "very cozy all night." Below is a photo of the two from a post-Grammy party.
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