Prince William and Prince Harry have very different personalities. But when they were younger, it was the Duke of Cambridge who was more known as a goofball.

As the royal siblings got older, the realities of life dawned on the second in line to the throne. As the future King of Great Britain, he has become more serious and quite standoffish.

While in Pakistan, a body language expert described one of Prince William’s favorite habits: mouth-puckering. Even when he was still a child, photos of the dad of three showed him with his lips closed and only slightly lifted in the corners.

“The mouth-puckering suggests an amount of impatience and the lack of a social smile does make him look more like a rather unapproachable and possibly tetchy but very focused businessman,” body language expert Judi James told Express.

James also said that Prince William’s demeanor usually makes him look like a focused businessman. In the past, another source described the Duke of Cambridge as controlling and standoffish because unlike his younger brother, Prince William isn’t warm and fuzzy.

In the documentary “Reinventing Royals,” Sarah Le Marquand from the Daily Telegraph Australia explained her observations.

“[He is] not quite the warm and fuzzy character that maybe some of the people lining up in the streets think he is… For all of his easy-going façade, Prince William is obviously a very controlling character,” she said.

ITN reporter Tim Ewart said that the Duke and Duchess of Cambridge were the first two people that he covered who didn’t engage in a conversation with him at all.

Prince Harry, on the other hand, has become such a fun character. But he is still very professional and dependable. According to royal author Penny Junor, Prince Harry is also not as reserved as Prince William.

“Harry makes you laugh within seconds. He will make a joke at his own expense. He will make a joke at your expense. It’s like talking to a normal person. With the Prince of Wales and with William, there’s always a feeling that they are somebody a little bit different,” she said.

Prince William
Prince William attends the unveiling of The Victoria Cross Commemorative Paving Stones representing each of Birmingham's 1st World War recepients at the Hall of Memory, Centenary Square on Dec. 7, 2015 in Birmingham, England. Getty Images/Richard Stonehouse