Comedians make their living taking snipes at celebrities, but sometimes they go too far for a laugh.
Joan Rivers got put in her place by Rihanna this week after the brash Fashion Police host chided the pop star for confessing to Oprah that she'll always love her ex Chris Brown. "Wow u really do get slow when you're old huh?" RiRi responded, before suggesting Rivers "slap on some diapers."
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