The first is a black-and-white image of a young Charles and his sister, Princess Anne, being pushed on a wooden swing by their father, Prince Philip. The second shows Camilla with her father, Bruce Shand, on her wedding day to Charles in 2005. “To all Dads everywhere, we wish you a happy Father’s Day today,” the caption of the post read.

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.

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.

The Royal Family assembled on the Buckingham Palace balcony following the Trooping the Colour parade marking King Charles III's official birthday. The monarch and Queen Camilla took centre stage as they awaited an aerial display featuring the Red Arrows,

Britain's King Charles and Queen Camilla ride a carriage as part of the Trooping the Colour parade which honours King Charles on his official birthday, in London, Britain,. REUTERS/Isabel Infantes LONDON (Reuters) -Britain's King Charles and other senior royals wore black armbands at the "Trooping the Colour" military parade on Saturday as a mark of respect for the victims of the Air India plane crash.