Dannii Minogue is said to be furious that Cheryl Cole is proving to be so popular on The X Factor.
The Australian singer, 36, is worried that fellow judges Simon Cowell, 48, and Louis Walsh, 55, think the Girls Aloud star more talented. And insiders say Dannii's insecurity is causing a rift on set.
‘They’re both professionals during filming, but when the cameras stop rolling it’s clear they have a big problem with one another,’ a source tells the News Of The World.
‘We’ve heard plenty of snide comments backstage. Simon has tried his best to intervene but there’s nothing he can do.
‘He and Cheryl get on like a house on fire. He thinks she’ll be a big hit with the viewers.’
Cheryl, 25, joined the ITV show last month after Sharon Osbourne, 55, quit in a row over pay.

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