Prince William turns 33 on 21 June, which coincides with this year's Father's Day in the UK.
The Duke of Cambridge has extra reason to celebrate, after welcoming his second child, Princess Charlotte, with wife the Duchess of Cambridge earlier this year.
Prince William turns 33 on 21 June
To honour the dad-of-two's birthday, HELLO! Online has gathered ten facts about the future King you may not have known.
1. William was born on 21 June, 1982 at St. Mary's Hospital, Paddington, London, the same hospital where his wife Kate gave birth to both their children.
The Prince was born in the same hospital as his children, George and Charlotte
2. The popular Prince is a supporter of the arts and in 2010 he became the new president of the British Academy of Film and Television Arts (BAFTA).
3. The second-in-line sports a Harry Potter-style scar on his forehead, after he was accidently hit around the head with a golf club by another school pupil in 1991.
William and Kate married on 29 April 2011
4. In November 2010, the palace announced the royal was to marry long-time love Kate Middleton. Six months later royalty from around the world gathered to witness the wedding ceremony, which was watched by a reported 1.5 billion people. On the morning of the wedding, it was confirmed William and Kate would be known as the Duke and Duchess of Cambridge.
5. The night before his royal wedding, the Prince revealed he only got 30 minutes sleep: "I hadn't slept at all that night because obviously all the crowds were on The Mall," he said. "They were singing and cheering all night long. So, the excitement of that, the nervousness of me, and everyone singing meant I slept for about half an hour."
6. His former colleagues revealed they often played pranks on the Prince: "We spent a few pounds on Kate and William memorabilia and strategically secreted it around the place so he might open a locker and find stuff, or find his own face on a cushion or see his own face on a cup when you give him a cup of tea," one revealed.
The royal couple will be celebrating Father's Day on the same day as William's birthday
7. At the time of writing, there are 6,342 items listed under 'Prince William' on eBay UK, with items including Christmas cards, figurines, magazines with William on the front, glossy post cards and royal wedding spoons.
8. When asked what he would do if he was invisible for the day, he said "I'd probably go into the newspaper office and listen to all the stories they tell about me."
9. William's full title is 'His Royal Highness Prince William Arthur Philip Louis, Duke of Cambridge, Earl of Strathearn, Baron Carrickfergus, Royal Knight Companion of the Most Noble Order of the Garter'.
The future King is father to Prince George and Princess Charlotte
10. In July 2013, the Duke and Duchess welcomed their first child, Prince George, who was followed by Princess Charlotte in May of this year.