Tomorrow the Royal Family's thoughts are likely to turn to the Queen's late beloved husband Prince Philip as they mark the first anniversary of his passing.
The Duke of Edinburgh passed away at Windsor Castle following a bout of ill health aged 99.
As the family remembers Philip, they may reminisce about the happy times they spent with him, especially during the summer holidays at Balmoral.
And in a documentary last year, several of his grandchildren, including Prince William shared a particularly happy memory of a food prank Philip used to pull while at the royals' Scottish retreat.
But it seems the Queen didn't always find the funny side.
In the documentary Prince Philip: The Family Remembers, William revealed how his grandfather would get family members to hold a tube of mustard in their hands before removing the lid.
He recalled: "He would squish your hands together to fire the mustard up into the ceiling.
"He used to get into a lot of trouble with my grandmother for covering most of the places where we had lunch with mustard."
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Meanwhile, his other grandchildren, Peter Phillips and Zara Tindall also touched upon their grandfather's fondness for the mustard prank.
Zara explained: "I can’t remember exactly what he says but he ends up slamming your hands together…. It goes all over the ceiling."
In the same documentary, the royals also spoke about Philip's quick wit and how it stayed with him to the final days of his life.
In one moving interview, his oldest son Prince Charles recalled the last time he spoke to his father - the day before he died at Windsor Castle.
Charles said he rang him to ask him what he would like to do to celebrate his 100th birthday.
The Prince of Wales described how he tentatively broached the subject with his father, daring to suggest a party he knew Philip was not keen on.
"We're talking about your birthday," Charles said he told his dad.
Knowing his father was slightly hard of hearing, he then repeated himself more loudly, emphasising: 'We're talking about your birthday! And whether there's going to be a reception!'
To which Charles said Philip replied sharply, without missing a beat: "Well, I've got to be alive for it, haven't I?"
Charles then said: "I told him 'I knew you'd say that!'" and added that it was a happy memory.
