Princess Charlotte mirrored her great aunt, Princess Anne, as she stepped out to celebrate the King's offical birthday at Trooping the Colour on Saturday.

The British royals were out in full force at Trooping the Colour on Saturday. But did you spot that Lord and Lady Frederick Windsor were also in attendance?

Senior working royals including Prince William, Kate Middleton, Princess Anne, Prince Edward and Queen Camilla will reportedly take part in the king's birthday parade.

While the cost of this year’s event has not been confirmed, it was revealed by the Ministry of Defence in 2021 that it cost them £59,662.70 that year for Trooping the Colour - a fact that was revealed after a freedom of information request.

"Set with diamonds, sapphires, rubies and emeralds, the bejewelled piece features the cypher of her father, King George VI," Zack Stone, a fine jewelry expert from U.K. retailer Steven Stone, shared with WWD.

Ahead of Saturday's festivities, King Charles III also honored a handful of celebrities and public figures, including David Beckham, Gary Oldman and Elaine Paige.

Trooping the Colour, a centuries-old royal tradition that dates back to the 17th century, is set to take place this weekend.