Crisis-hit royals’ new nightmare: Kate Middleton’s loose cannon Uncle Gary becomes Big Brother star

He describes himself as “a toddler on sugar,” has been caught in a cocaine sting by an undercover reporter and is a multi-millionaire who pleaded guilty to assaulting his fourth wife.

Uncle Gary Goldsmith is Princess Kate’s worst relative, even by his own admission, with a “self-destruct mode” he can’t control.

So the last thing Britain’s crisis-hit royal family would need right now is a loose cannon like him dropping truth bombs on television.

But that is precisely what is happening — just as the royals grapple with Princess Kate’s mysterious prolonged absence due to an unknown health condition, and King Charles’ cancer.

Uncle Gary, Kate’s mother’s younger brother, made his first appearance on Britain’s Celebrity Big Brother on Tuesday night and made an immediate splash with his loud personality and comments about his royal relations.

While Gary claims to adore his niece, in an interview before he went in, he threw lighter fuel on her and Prince William’s feud with Prince Harry and Meghan Markle by saying of them: “Throwing your family under the bus just seems inappropriate.”