Mike Tindall has hinted he keeps in touch with Prince William and Prince Harry via a WhatsApp group.

Mike Tindall

Mike Tindall

The 39-year-old former rugby star has claimed he and his wife Zara Tindall - who have four-year-old daughter Mia together and are expecting their second child - keep in touch with their family in a large group on the social media app, and after mentioning Zara's "cousins", the sports star has sparked speculation he may be talking about the two Princes.

Mike said during an interview with the Daily Mirror newspaper: "Me, my brother and then a few of Zara's side like her brother Pete and the cousins are on WhatsApp groups.

"I wouldn't say we're cutting edge, but it's just easier for some reason on WhatsApp. I'm in about 25,000 groups.

"You might do it for a get-together and just stay on the group, and occasionally people will post. You're scared to leave because you don't want to be seen to be rude."

Although he didn't name the royal brothers, Zara is the daughter of Princess Anne, who is in turn the daughter of Queen Elizabeth and sister of Prince Charles, which makes her cousin to William and Harry.

One thing Mike and Zara, 36, might have shared on their chat with her famous family, however, is the news of their impending arrival.

A spokesperson for the happy couple confirmed the news earlier this month, and although it isn't known when the tot is expected to be born, it's an exciting time for the royal family as Zara's cousin Prince William and his wife Duchess Catherine announced last year that they are set to welcome their third child into the world in April, while William's brother Prince Harry is set to marry his fiancée Meghan Markle this spring too.