Kelly Osbourne Slams Christina Aguilera: She's a 'Fat B----!'

Kelly Osbourne has never been a fan of Christina Aguilera, but the 26-year-old took their feud to a new level during a recent episode of E!'s "Fashion Police."

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After Joan Rivers, 78, said Aguilera looked "stuffed into" a Givenchy LBD at an event in Munich, Germany last month (and likened her to "Snooki's Scandinavian cousin"), Osbourne chimed in: "Maybe she is just becoming the fat b---- she was born to be. I don't know. She was a c--- to me. And she bought my house!"

Osbourne's digs at 30-year-old Aguilera's fluctuating weight didn't end there. "She called me fat for so many f------ years," Osbourne continued, "so you know what? F--- you! You're fat too."

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Ironically, Osbourne opened up to Us Weekly in Feb. 2010 about her own weight struggles. "I took more hell for being fat than I did for being an absolute raging drug addict. I will never understand that," the reality star, who checked into rehab for drug and alcohol addiction three times, said.

The 5-foot-2 Osbourne, who once weighed "almost 160" pounds, recalled once walking down the street when "some horrible obnoxious teenager screamed out a car window to me, 'You're fat!' I went to my parents [Sharon and Ozzy] bawling, 'I would rather be called ugly than be called fat!'"

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After years of yo-yo dieting, Osbourne shed more than 48 pounds thanks to her 2009 stint on "Dancing With the Stars" -- and she's kept it off since!

"I just commit to half an hour a day. It doesn't seem overwhelming and I can handle that," she told Us in Oct. 2010. "I do half an hour on the treadmill and when I feel like doing more, I'll do a few sit-ups and some weights."

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