Kate Middleton's 'Black Sheep' Uncle Warned Not to Spill Family Secrets Ahead of 'Celebrity Big Brother' Debut

Kate Middleton's uncle has been "read the riot act" by her parents before his debut on Celebrity Big Brother amid fears that he could spill family secrets on the drama-packed reality show, RadarOnline.com has learned.

Gary Goldsmith is brother to Carole Middleton, Kate's mother, and is claimed to have secured a substantial deal with ITV for his appearance.

Cameras will be rolling 24/7 on the new rebooted series, which premieres on Monday and will welcome a group of stars into the Big Brother house, where they'll spend several weeks living together, taking part in challenges, and competing to be crowned the winner.

Among those joining Goldsmith will be TV presenter Fern Britton, Coronation Street's Colson Smith, Love Island's Ekin-Su Culculoglu, YouTube star Zeze Mills, and Strictly Come Dancing's Nikita Kuzmin.

"He wants to defend his family. Gary wouldn't do anything to embarrass Kate or William, who he thinks a lot of," one insider told The Sun.

However, Carole and Kate's father, Michael, are worried that Goldsmith will undoubtedly air some dirty laundry despite his good intentions.

"It is infuriating to them. Kate doesn't need this stress," said the source. "With Kate being out of the public eye at the moment and William shouldering a lot, the last thing they want is for Uncle Gary to be causing any embarrassment on television."

Kate underwent abdominal surgery in January and will be MIA until after Easter, Buckingham Palace shared in a prior statement.

Earlier today, the Princess of Wales reemerged for the first time since her procedure and was seen riding passenger on Monday in a car driven by her mother near Windsor Castle in the U.K.

Although Kate's loved ones are gearing up for some potential drama up ahead, "Gary has said he knows what he is doing and has told his friends he'd never do anything to hurt his family," said an insider who claims the Duke and Duchess of Sussex may not be so lucky.

"Prince Harry and Meghan Markle are more than likely going to be in the firing line as Gary has made no secret about how little he likes them," the insider added.

Goldsmith previously spoke out against claims made by the Sussexes in October, slamming Harry for writing about the rift between Meghan and Kate over bridesmaid dresses.

He denied that Kate is a "drama queen" and declared, "I'm particularly appalled by his vile confection of half-truths and complete fabrications because Kate is my adored niece."

"She'd never pile more pressure on a bride," Goldsmith wrote in his Daily Mail column. "After all, she knows the tensions involved when you marry into the Royal Family all too well."

Goldsmith stated that Harry's memoir, Spare, only furthered the divide in his family, adding, "All it will do is make the gaping chasm between them unbridgeable."

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Kate's uncle has since been spotted entering a London hotel after arriving at the ITV studios.