Prince William’s Funniest Moments

Prince William Chris Jackson/Getty Images

Prim and proper? Not so much.

Though he's extremely dedicated to his royal duties — including his career as a RAF search and rescue pilot — Prince William has never taken himself very seriously.

The Duke of Cambridge, who celebrates his 30th birthday Thursday, has been known to publicly poke fun at himself — and his family members — during interviews and formal engagements.

"I'm always open for people saying I'm wrong, because most of the time I am," Will told the BBC in 2004. When asked about his 86-year-old grandmother, he admitted, even as an adult, he makes it a point to stay on her good side. "You know when you're in her bad books," he has said of Queen Elizabeth. "I’ve seen the way the corgis get told off when they're in trouble."

When it comes to celebrating the big 3-0, a palace insider told Us Weekly Thursday that his wife of over a year, Duchess Kate, has been "planning a small dinner party with their friends and some family," at dad Prince Charles' countryside home.

A Buckingham Palace aide confirms the plans for Will's royal birthday bash. "William is working as usual during his birthday week," the spokesman reveals. "Tonight he will have a private celebration with family and friends."

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