Photo: Karwai Tang/WireImage

LONDON, ENGLAND - SEPTEMBER 28: (L-R) Catherine, Duchess of Cambridge, Prince William, Duke of Cambridge, Camilla, Duchess of Cornwall and Prince Charles, Prince of Wales attend the “No Time To Die” World Premiere at Royal Albert Hall on September 28, 2021 in London, England. (Photo by Karwai Tang/WireImage)

Happy birthday,King Charles III!

Prince WilliamandKate Middletonreleased a special message to commemorate the monarch’s 74th birthday on social media Monday. The Prince and Princess of Wales, both 40, were the first members of the royal family to do so.

Buckingham Palace similarly wished Charles a happy birthday Monday,tweetinganother smiling photo of the sovereign along with a peek behind the scenes of related tributes in London. The King’s Troop Royal Horse Artillery fired cannons in Green Park at midday, and the Household Cavalry Band delivered an epic rendition of “Happy Birthday” during the Changing the Guard ceremony outside Buckingham Palace.

Charles has previously hinted that he’s lighthearted about the idea of growing older. Last month, the King had the perfect reply for a curious schoolchild who wondered aloud how old he was during a stop in East London.

“You can have a guess, you can have a guess,” the monarch replied with a laugh.

This is Charles' first birthday since acceding as King following the death of his motherQueen Elizabethin September. While his coronation has been set for May 6, the palace has yet to release details about aTrooping the Colourcelebration in his honor, as his mother did as monarch for 70 years before him.

King Charles III.Hugo Burnand-Pool/Getty

Prince Charles, Prince of Wales poses for an official portrait to mark his 60th birthday, photo taken on November 13, 2008 in London, England.

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In a twist of history, King George II kicked off the summer tradition — a military parade in the monarch’s honor — because, like Charles, his birthday was in the chilly month of November, according toRoyal Museums Greenwich. In modern custom, Trooping the Colour has been held on the second Saturday in June.

source: people.com