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By Kat Giantis

Will it be a really silent night this Christmas for Kelly Osbourne and her big sis? So claims the London Daily Mirror, which says an ongoing cold war between the size 2 starlet, 26, and her spotlight-averse sister, Aimee, 27, has put a damper on the family's holiday festivities.

"Aimee and Kelly haven't spoken for months after an almighty row," says a source. "They've always had a challenging relationship, but this last row seems to have tipped them both over the edge."

RELATED: Kelly reveals how she lost 50 pounds

According to the paper, the siblings' supposed feud means that parents Ozzy and Sharon will have to divvy up their time on Christmas Day, the same way they allegedly did on Thanksgiving, joining Aimee in the morning and Kelly in the evening.

"It's become a nightmare situation for the whole family. Sharon's distraught about what's happened. Neither girl will back down," continues the snitch. "Kelly's been telling her friends that the family will have to get used to the fact that they just don't get on ... Hate is a strong word. But they really don't like each other."

But that's news to Kelly, who has been hanging with Miley Cyrus while filming "So Undercover" in New Orleans.

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She took to Twitter on Sunday night to assure everyone that love is all around in the Osbourne household this holiday season.

"We are both spending Xmas together in the UK!" wrote Kelly. "I love my sister."

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