Here’s a little celebrity-attacks-celebrity story that involves a little unpleasant body-related name calling:

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.

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 bitch she was born to be. I don’t know. She was a c**t 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***ing years,” Osbourne continued, “so you know what? F**k you! You’re fat too.”

What do you think of Kelly’s reaction? Justified or should have taken the classy road?