Britain's Prince Charles used to embarrass his sons William and Harry when they were at school.
Prince William, Duches Camilla, Prince Charles and Prince Harry
The royal siblings have revealed they were often left red-faced in front of their class mates because their dad - the eldest son of Queen Elizabeth and Prince Philip - would burst out into a fit of laughter at all the wrong times.
Speaking to comedy duo Ant McPartlin and Declan Donnelly as part of the forthcoming TV documentary, 'When Ant and Dec Met the Prince: 40 Years of the Prince's Trust', William, 33, explained a time when Charles fell into hysterics when the special effects malfunctioned at his school play.
The flame-haired hunk, who now has two children of his own George, two, and seven-month-old Charlotte, with his wife Duchess Catherine, then went on to joke that it's a family trait to find the funny side when "when things go wrong."
Despite often taking a humorous attitude when things fail to go his way, William and Harry, 31, later praised their father for being "incredibly hard-working."
The 90-minute documentary, which is set to reveal a different side to the heir-to-the-throne, also sees Charles speaking lovingly about his "darling" second wife Duchess Camilla, 68, who he married in 2005, according to the Daily Mail newspaper's Event magazine.
'When Ant & Dec Met the Prince: 40 Years of the Prince's Trust' will air on January 4 at 9pm on ITV.
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