On Sunday, Prince William not only celebrated his 38th birthday, but his jubilation was doubled as he marked the occasion of Father's Day as well. On this special day for Prince William, the Duke and the Duchess of Cambridge released a set of never-before-seen pictures showcasing Kate Middleton's photographic skills and an adorable moment between the royal father-son duo.

In the honour of Father's Day, Kensington Royal, the duke, and the duchess' official Instagram account posted an unseen picture of Prince William and his father Prince of Wales taken by Kate Middleton in the year 2019. The picture shows the father and son hugging each other adorably.

The second picture, in honour of the duchess' father, shows her younger self sitting in the lap of Michael Middleton.

"Happy Father's Day!

1. The Duke of Cambridge with The Prince of Wales at Sandringham in December 2019

2. Michael Middleton with his daughter Catherine

The first photo was taken by The Duchess of Cambridge" reads the caption on the post.

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Happy Father’s Day! • 1. The Duke of Cambridge with The Prince of Wales at Sandringham in December 2019 2. Michael Middleton with his daughter Catherine First photo taken by The Duchess of Cambridge

A post shared by Duke and Duchess of Cambridge (@kensingtonroyal) on

Fans were delighted to see these pictures and left some heartfelt comments for the royals. "What a great pic of His Highness Prince of Wales and Duke of Cambridge," one follower wrote. "What a wonderful photo. Pure love & respect," said the other one.

Meanwhile, fans were impressed by Kate's photography too and sent some appreciation her way through their comments. "Kate is TALENTED. Please share more photos from the Duchess!" a fan said in the comments box.

Meanwhile, Charles and Camilla, the Duchess of Cornwall, used the same picture to send out William's birthday wishes.

"Wishing a very happy birthday to The Duke of Cambridge today! This new picture of The Prince of Wales and his son was taken by The Duchess of Cambridge last December," Clarence House said in the caption.

British royal family at Commonwealth Day service
There were reports of splits within the royal family, and a growing rift between Harry and William. Photo: POOL / Phil Harris

In addition, the Prince of Wales account also shared a gorgeous black and white photo wishing Charles' father Prince Philip a Happy Father's Day. In the picture taken in 1951 at Clarence House one can see Philip holding Charles and Queen Elizabeth II holding Princess Ann. The second picture posted on the account shows the heir to the throne with both his sons William and Prince Harry at Cirencester Park Polo Cup in 2004.