If you listen to Kelly Osbourne's yapping, Christina Aguilera called her fat for years back when Christina didn't demand a fully stocked buffet in her dressing room at all times. Now that Christina uses her deep-fryer more than a mirror, she's conveniently changed her tune about this fat thing. She told reporters at a TCA conference Friday, "I've been in this [business] for a long time. I came out on the scene ...