01/07/2014 08:21 BST | Updated 01/07/2014 10:59 BST

Cheryl Cole Celebrates With 'X Factor' Judges Simon Cowell And Mel B... But Where's Louis Walsh? (PIC)

Cheryl Cole celebrated her birthday in style on Monday afternoon, taking time out from the ‘X Factor’ auditions to enjoy some downtime with her fellow judges aboard a private jet… but it looks like there was one notable absence.

While Mel B and Simon Cowell got into the party mood, posing for a selfie in brightly coloured party hats while on a flight to Edinburgh, it seems as though Louis Walsh’s invitation was lost in the post.

Louis and Cheryl’s working relationship doesn’t appear to be going brilliantly since she rejoined the panel, with Simon previously saying that Cheryl didn’t even want the Irish judge to return to the show for this year’s series.

It was also recently reported that the ‘Crazy Stupid Love’ singer went as far as refusing to sit next to him on the panel, and she told presenter Graham Norton during an interview on his talk show that their relationship had been “frosty” when auditions kicked off.

It’s now been claimed that Louis is starting to feel left out on the panel, with Mel and Cheryl growing closer than anyone had expected them to.

A source close to Louis told The Mirror: “He had joked that it would be Cheryl who was the one left out on her own. He has been friends with Simon for what seems to him like a lifetime and he thought he and Mel would be mates and that she and Cheryl would clash.

“But things have worked just the opposite… It definitely isn’t how he thought it would be.”

Meanwhile, a cryptic tweet from Mel has sparked rumours that she may be joined by her old friend Victoria Beckham at the judges' houses stage of this year’s series of ‘X Factor’.

We wonder if she’ll be rocking a leaf bikini as a tribute to Sinitta...

Photo gallery Cheryl's 10 Best 'X Factor' Moments See Gallery

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