Prince William has revealed the signature prank pulled frequently by his late grandfather which used to get him in "a lot of trouble" with the Queen.
In a preview for the BBC documentary Prince Philip: The Royal Family Remembers – which features interviews with more than a dozen members of the royal family – William explained that his grandfather's trick involved a tub of mustard and a lot of mess.
"He used to take the lid off and put it in your hands … and then he'd squish your hands together to fire the mustard on to the ceiling," he said.
"He used to get in a lot of trouble from my grandmother for covering most of the places we had lunch and things with mustard on the ceiling … He enjoyed those jokes, he enjoyed messing around the children and being a grandfather."
The mustard prank memory was also shared by William's cousin, Zara Tindall.