Kelly Osbourne vs. Christina Aguilera and Lady Gaga
Back in the day, Christina Aguilera gained attention for calling Osbourne fat, but now that Osbourne's trimmed down, she's turned the tables on the former Voice coach. For someone who's undergone such intense physical scrutiny herself, you'd think Osbourne would learn how hurtful comments like that are. Unfortunately, that hasn't stopped Osbourne from also calling Lady Gaga a butterface and jokingly asking if she was pregnant. Gaga refused to play along, writing an open letter to the star and asking for a ceasefire.
Photo By: Jamie McCarthy/Getty Images; Donato Sardella/WireImage; Olga Bermejo/FilmMagic
Photo Credits: Richard Cartwright/ABC via Getty Images; FOX; Eike Schroter, ABC; Axelle/Bauer-Griffin, FilmMagic; Daniel Zuchnik, WireImage; HBO; FX; Steve Granitz/Getty Images; Jeff Kravitz/Getty Images; Alberto E. Rodriguez/Getty Images