Mike Tindall's cheeky nickname for Prince William that sent tongues wagging

who today celebrates his 45th birthday, has a naughty nickname for - and it's previously landed him in hot water.

While at public events, members of the are generally referred to by their official titles, but behind closed doors, there is apparently a little less formality. Indeed, from to BeaBea (Princess Beatrice), the family is known to be rather fond of affectionate nicknames.

However, the moniker Mike thought up for the future King was less than flattering, and led to his wife Zara Tindall warning him he'd end up in 'so much trouble'. The rugby star turned Royal 'fessed up to the nickname on a special podcast he and Zara recorded about the late Rugby League legend Rob Burrow, who sadly passed away in June following a Motor Neurone Disease (MND) diagnosis.

Naturally keen to know about royal life behind the pomp and pageantry, Rob asked whether Mike and Zara had any nicknames for their famous family members - and ended up learning plenty about what a night out with Prince William might look like.

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, Mike revealed: "For the Prince of Wales, he is known as One Pint Willy. He is known to me as One Pint Willy because he is 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 definitely give away for the Prince of Wales." However, after the revelation, a giggling Zara warned her husband: "Oh my god. You are in so much trouble."

Fortunately, William saw the funny side of Mike's admission as several weeks later, to present Rob and his former teammate Kevin Sinfield with their CBEs for their outstanding efforts to raise money and awareness of motor neurone disease.

As Rob welcomed William to Leeds, he alluded to the secrets Mike had told him on his podcast and it prompted William to say as he giggled: "It was you who got the nicknames out of him - he apologised to me about that. When I saw him, I said Mike, when you say you're not going to mention your nicknames doesn't mean you mention mine, it's not fair'. I'm sure it's quite fun with Mike."

This comes as Prince William issues a defiant message to critics who have taken issue with him leading his , which aims to eradicate homelessness in six locations around the UK. In a new teaser clip from an upcoming documentary about the project, an interviewer probed: "There will be some people who might question whether you’re the right person to lead this project and its efforts to end homelessness. How would you respond to that?"

William then responded: "I think everyone having a right to a safe and stable home benefits us all. I come with no other agenda than desperately trying to help people who are in need. And I see that as part of my role, is that, why else would I be here if I’m not using this role properly to influence and help people where I can?"

Do you have a story to share? Email me at julia.banim@reachplc.com. Follow Mirror Celebs on , , , , , and

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