Sharon Osbourne has been involved in a number of bust-ups with her fellow X Factor judge Dannii Minogue.
Apparently Sharon is furious that Dannii has joined the panel for the new series, because she does not like sharing the spotlight with the Aussie singer.
An ITV source told The People: "Sharon is acting like a cow and poor Dannii doesn't know what's hit her. Sharon's nose has been well and truly put out of joint by the arrival of Dannii. In previous series she has been the star of the show."
The People reveals that Dannii burst into tears after a heated row with Sharon at the Manchester auditions, and the pair refused to speak to each other at boot camp.
A spokesman for Sharon said, "Naturally there is rivalry as they want to win. But they have a mutual respect for each other. Any barbs are in jest."