Mike Tindall, former rugby champ, joined the royal family in 2011 when he tied the knot with Zara Tindall, the daughter of Princess Anne. Their royal wedding took place just three months after William and Kate, Prince and Princess of Wales, were wed. Even back then, it was clear that the two men were destined to become friends.

A sign of any good friendship is the ability to tease one another. And, surprisingly enough, Prince William and Mike have some of the most hilarious bits of banter we've yet to see from a royal friendship. Royal expert Rosa Silverman revealed that Mike had a friendly greeting prepared for William's 27th birthday. Per the Telegraph, Mike was overheard saying "How's it going, baldy?" when he saw William, and William just as cheekily replied with "What's it to you, fatty?"

While making an appearance on fellow rugby pro Rob Burrow's "The Total Sport Podcast," Mike poked fun at Prince William for being a lightweight when it comes to drinking alcohol. Tindall couldn't help but laugh as he revealed that his nickname for Prince William is "One Pint Willy," a funny name given to his friend for his inability to handle more than a few drinks. The comical podcast had both Burrow, Mike, and his wife Zara in absolute stitches. It was a funny moment that shows just how well Mike and William get along behind the scenes.