Prince William apparently simmered with jealousy over an incident involving his wife, Kate Middleton, and her celebrity friend, Jack Whitehall. The professional British comedian himself recounted the details of how he became the subject of a passive-aggressive attack from the Duke of Cambridge.

Daily Express reported that Kate has been Whitehall's "first crush" since they attended Marlborough College together. He confessed this in public at one Royal Variety Performance, with the Duke and Duchess of Cambridge in the audience, but the flirting on stage apparently didn't sit right by Prince William.

Whitehall shared this anecdote at The Jonathan Ross Show. He confessed that Prince William called him out after his performance ended.

During the line-up where the royals greeted the people behind the event, the Duke of Cambridge apparently "confronted" Whitehall. He told the comedian that he actually found his performance "very, very funny" but Whitehall said he felt a different vibe and understood the royal's statement to mean that he's in big trouble and he'll lose his head.

Whitehall, of course, is only joking about Prince William's threat to behead him. In reality, he said that he never stood a chance with Kate because she was six years older than him and she won't give a kid with a head brace in school another look.

It's not the first time Whitehall has cracked a joke about the royal family or Kate. In an episode of The Graham Norton Show, the comedian also talked about how the press writes about the Duchess of Cambridge as a commoner, as if she came from the ghetto. In truth, Marlborough College is full of kids from privileged families.

Whitehall also made a naughty joke about hoping he dated Kate during his school years. He said that, if that happened, for the rest of his life he'd brag to friends about once dating the future Queen consort. The actor said that he knows of some friends who did date Kate before she met Prince William.

The comedian, however, joked that he's the one graduate of Marlborough College who might be considered as the school's "dirty little secret." Whitehall said that he has yet to get his photo printed on the school prospectus because he hasn't achieved the level of success and influence as the Duchess of Cambridge.

Apparently, Kate, even then, excelled as a student. Her records at the school's sports are still on the board and some are over 20 years old.

After Kate left Marlborough College, she attended St. Andrews where she met and then had a relationship with Prince William. Then, as they say, the rest is history.