Prince William turned heads with a major switch-up of his appearance on Monday as he took to Instagram alongside his wife the Princess of Wales to congratulate Team GB for their success in the Paris Olympics.
It took royal fans mere seconds to notice the unmissable change in Prince William - that the historically cleanly-shaven royal was sporting a beard for a rugged edge.
It has been many years since the royal father of three has rocked facial hair in public, but he is not the first Prince of Wales to do so. In fact, it may well be that Kate's husband was inspired by a bearded moment his father King Charles indulged in in his earlier years - and the likeness is uncanny!
The then-Prince Charles looked strikingly similar to his son in April 1976 when he rocked what is known as a smart naval beard to the Badminton Horse Trials.
A 'naval beard' as it has become known, stems from the type of facial hair which is permitted in the Royal Navy - a full beard and mustache which join together and cover the jawline. Charles qualified as a helicopter pilot in 1974 before joining 845 Naval Air Squadron. He left the Navy in December 1976.
The late Queen's son's bushy facial hair accompanied his mop of dark hair which sat beneath a tweed flat cap.
Charles was spotted later that day, having earlier ridden on horseback, in a smart double-breasted coat which suited his new appearance.
The monarch has opted for a cleanly shaven look ever since, much like his eldest son who has made a few exceptions to the rule along the way.
The future king stepped out on Christmas Day in 2008 for the annual Christmas Day Church Service at St Mary's Church on the Sandringham estate sporting a beard but has stuck to a hairless look for public engagements.
Since then, his brother Prince Harry has carried the baton for beard-sporting royals who even rocked the bristly look on his royal wedding day to Meghan Markle in 2018.
Harry's wedding day beard wasn't without its controversy. The facial hair sat in direct opposition to military protocol as the groom was set to wear the frock coat uniform of The Blues and Royals which had to accompany a bare face.
As a result, the Duke of Sussex had to get permission from his grandmother Queen Elizabeth II. "I didn't want [Meghan Markle] coming down the aisle and seeing a total stranger," Harry wrote in his memoir Spare, explaining the reason he asked the Queen's permission to keep his beard.
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The Duke of Sussex also revealed William's thoughts on his beard. "Ah—there it was," Harry penned. "After he's come back from an assignment with Special Forces, Willy was sporting a full beard, and someone told him to be a good boy, run along, and shave it. He hated the idea of me enjoying a perk he'd been denied."