Mike Tindall shares a close bond with his cousin-in-law, Prince William and William's wife, Kate, so much so that Mike has a rather cheeky nickname for the future King.
The former rugby star and his equestrian wife, Zara Tindall, appeared on Rob Burrow's podcast, which aired on Wednesday.
The couple were asked about their nicknames for members of the royal family, to which Mike confessed: "The Prince of Wales is known to me as One Pint Willy because he's not the best of drinkers, coming from a sport where it is built on the social aspect and a couple of beers being sunk quite often. That is one I will give away for the Prince of Wales."
Laughing he said: "It's out there now, sorry sir."
Zara added: "You're in so much trouble!"
The Prince and Princess of Wales made a guest appearance, along with Mike's mother-in-law, The Princess Royal, on The Good, The Bad & The Rugby podcast earlier this year.
Find out Kate's sporting regret in the clip below...
Mike and Zara, who have been married for over 12 years, also revealed their unusual pet names for each other.
Mike said: "We basically call each other munchkins a lot. I don’t know why that started but it has stuck. I will let Zara decide whether she wants to give away what I am down in her phone as..."
Giggling Zara replied: "When he's not listening to munchkin or Mikey, it becomes Michael Tindall when there's no response. He is in my phone as something else and it ends with kitten…"
Mike quipped: "You can fill the first word in!"
The sporty pair were also asked by former rugby star Rob about whether their three children, Mia, nine, Lena, five, and two-year-old Lucas will follow in their footsteps.
Zara, who won silver at the London 2012 Olympics in team eventing, said: "Potentially, maybe but I guess you never want to push them too much because they may not want to do any of it.
"I think we've tried to give them both sides of our sports. They all know how to ride, and they've been around the horses. They've also all played rugby to a certain level."
Meanwhile, Mike, who was part of the winning England World Cup rugby squad in 2003, has pinned his hopes on son Lucas becoming a professional golfer.
"The two-year-old is where I am pinning my dreams, I actually wanted his middle name to be Mulligan because if he did become a professional golfer, he would drop the Lucas and just become Mulligan Tindall. I thought that would be the best golfing name ever. Plus, Mulligan means the offspring of a balding man, so that was perfect!"
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