Sunday, June 21 was a busy day for the Royal Family. Not only did they join the world in celebrating Father's Day 2020, but it was also Prince William's 38th birthday!

In tributes shared across the royal social media pages, throwback photos featured prominently. But one new photo stuck out among the collection: a previously unseen shot of Prince William holding Prince Charles in an affectionate embrace.

Prince William & Prince Charles hug in new photo by Kate Middleton

Duchess Catherine has struck once again, receiving credit for the new photo, which she took at Sandringham in December 2019. Kate's Father's Day photo, meanwhile, was a childhood throwback snap with Michael Middleton.

"Happy Father's Day!," read the short but sweet caption on the Duke and Duchess of Cambridge's Instagram post.

Clarence House also contributed a pair of great throwback photos that show Queen Elizabeth II and Prince Philip caring for Charles and Princess Anne in 1951, as well as the Prince of Wales with sons William and Prince Harry at the Cirencester Park Polo Cup in 2004.

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"Whether you are a Father, a Dad, a Daddy or a Pa, wishing you a Happy Father's Day!," Clarence House captioned the post.

Queen Elizabeth II celebrates Father's Day 2020

Finally, the Queen shared to Instagram a set of archival images that see Prince Philip raising their four children, Charles, Anne, Andrew, and Edward.

The Duke of Edinburgh, a father of four, turned 99 years old earlier this month.

Happy Father's Day to the royal dads and all others alike!