Prince William celebrated his 41st birthday yesterday but this year was a particularly special occasion as it was his first in his new royal role.
The future King was appointed as Prince of Wales by his father King Charles who previously held the title before the death of Wiliam's grandmother Queen Elizabeth II last September.
This means that William is now heir to the throne and his new role has seen him take on more royal responsibilities alongside his wife Kate, Princess of Wales, the Mirror reports.
According to one body language expert, William is now at the "pinnacle" of self confidence and appears to have grown out of the anxious gestures he once shared with his younger brother Prince Harry.
Expert Darren Stanton explained: "He's become ever-so more statesman-like in recent years.
"We don’t see any of the old gestures from him that he previously displayed, which denoted a lack of confidence or feeling like a fish out of water.
"He's a completely different person from when he first started public appearances as a youngster.
"Some of the tell-tale gestures that we associate with William are what we call pacifying gestures, which are often used in moments of self-reassurance.
"We got these a lot with King Charles where he would put his hand inside his jacket.
"If you look at historic footage from Prince William and indeed Prince Harry, you will see that William inherited this gesture from his father.
"William often made this gesture whilst doing any public engagements or standing on the balcony with the Queen.
"William would also play with his cufflinks during his early years. Again, this is a self-reassuring gesture, designed to soothe ourselves when we’re in situations that we’re finding stressful or when we feel that we’re not in total control.
"Over the years he’s been placed in lots of social situations where anybody would probably feel a little bit anxious, however, we tend not to see that gesture as much now."
Mr Stanton opined that William's positive change in body language has been brought on by Kate Middleton who has also seen her confidence in the public eye grow.
Speaking on behalf of Betfair Casino, he added: "In terms of his development as a person, I think Kate has played a large part in his development.
"When they met the two of them were not that particularly confident people, however, they’ve both developed over the years.
"With respect to Kate, she has played a major part in his development as a person, as a future monarch, and certainly when it comes to his degree of confidence in the world.
"She too has developed greatly over the years, even more so than William. She started off quite introverted, not really wanting to get involved, and now she's become a more and more integral part of the royal family - especially since their marriage.
"These two are now considered to be the most senior members of the working royal family. I definitely believe Kate’s development of confidence has also helped William to feel more at ease."
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