Kelly Osbourne Disses Christina Aguilera On Air

Kelly Osbourne dissed former friend Christina Aguilera in a major way when she made a comment about her weight on air. Perhaps she's getting back at Christina's name calling before Kelly slimmed down? Find out more after the jump!

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On E!'s Fashion Police (via Radar Online), Kelly slammed Christina and called her a "fat bitch." Here's why: Kelly mentioned that Christina "called me fat for so many f***ing years so you know what? F**k you, you're fat, too."

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This is after Joan Rivers mentioned that Christina looked "stuffed into" a Givenchy dress at a Munich event last month and quipped she's like "Snooki's Scandinavian cousin." To that point, Kelly added, "Maybe she is just becoming the fat bItch she was born to be. I don't know."