The close relationship between Prince Charles and his sons is demonstrated in newly-released video footage, in which the three royals are shown enjoying a day on the polo field.
The tape, which shows the three men joking around with each other before and after the match, was recorded by an ITV crew to coincide with Prince William's 21st birthday.
In one highlight, William good-naturedly says to his 54-year-old father after the match: "I'm well surprised you scored a goal, actually." Charles replies with a smile: "I can do it even at my advanced stage of decrepitude."
Later, the Prince of Wales intervenes when Prince Harry winds Wills up by saying with a grin: "I nearly fell off my horse trying to get you to hit the ball and you missed it, spoon."
At this point, Prince Charles asks: "Spoon, did you say?". Harry quickly assures his dad: "Spoon. It's not a swear word."
But, like any father, the Prince of Wales ensures that he has the last word. "It isn't, I'm sure," he says, adding: "I do hope it isn't."