Prince William “relished the freedom” during a brief break-up with Kate Middleton, according to a body language expert.
Judi James was looking over footage of the future king and his brother, Prince Harry, during the Concert for Diana in 2007.
Held a decade after their mother’s death in Paris, William and Kate were going through a brief break-up as they were “finding themselves”.
During the concert William was spotted dancing with his arms outstretched which Judi said showed it was not always the younger brother who behaved embarrassingly.
She said: “This hilarious clip shows it wasn’t always Harry doing the comedy moments in the royal Firm and that older brother William was quite capable of embarrassing Harry with some uninhibited dad-dancing.
“There is the strong hint William is trying to boast to Kate that he is relishing his freedom and is capable of having the most fun time without her."
Speaking to the Express, she added: "His elbows are raised in geezer mode and his neck-wobble hints at a touch of rebellion. It must have been the tiniest of swan songs before settling down with Kate though.
"As a signal of making the most of the single, free lad’s life it failed hilariously. Kate was there behind him all the time and he clearly wasn’t suited to this kind of body language ritual."
Judi claims the Duke enlisted the help of Kate, who at the time was sitting a few rows behind the royals, to get her ex-boyfriend at the time to stop dancing.
She added "William seems to be aiming this dancing at his brother, egging him on to join in while Harry appears to be deep in a more serious conversation with Chelsy, his girlfriend at the time.
"Kate was several seats back, probably thanks to the infamous ‘break’ with William that year.
"It looks as though it was Chelsy who brought William’s attention-seeking dance ritual to Harry’s notice.
"Harry turns, straight-faced and his look is very much the look of a teenager whose dad is shaming them during a party."
It comes as Prince Harry and Meghan Markle have been warned they could 'upstage' the Coronation if they try to go big on Archie's birthday celebration.
The royals are said to be still considering the invitation to attend the ceremony in ten weeks' time.
The event clashed with their son Archie's fourth birthday, but they are determined to still mark the day even if they jet back to Britain.
If they are to return in early May, insiders say they still intend to throw a party for their son - just like they would have done in California.
