London — King Charles III, from a very young age, cut an isolated figure, according to those who knew him. 

"He was always just a little bit of an outsider to start with," Johnny Stonborough, who was a classmate of the now-king at Gordonstoun School in Scotland, told CBS News.

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Stonborough's recollection of his classmate is of a young prince who was far from popular during his school days.

"Nobody wanted to be his friend, because if you were his friend, you were then teased brutally for being his friend," said Stonborough.

Prince Philip, Charles' father, was one of Gordonstoun's first pupils after the school opened in 1934, and he sent his son to the famed boarding school at the age of just 13. 

Contrary to the late Duke of Edinburgh, who thrived at the school, Charles would later compare his time at Gordonstoun to being in prison. 

Stonborough told CBS News that he personally bore witness to the bullying endured by the future king. 

"We were playing rugby football and a couple of the boys decided that they were going to 'do' the prince, which meant beat him up," said the royal's former classmate. He said they then set on Charles, pulling his ears and punching him.

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"He never complained. He never said a word," said Stonborough. "And if I hadn't actually seen it, nobody would know about it."

The king's struggles seemed to continue right into his university days. 

"I haven't made a lot of friends, if that's what they mean, and I haven't been to a lot of parties," Charles said in response to a question while he was a student at the University of Wales. "I've had a lot of other things to do."

Life at home with his family didn't seem to be much easier for Charles. 

His mother, the late Queen Elizabeth II, was described as a distant mother, and Prince Philip a harsh father, in a 1994 biography of Charles. 

Public comments by the future king have also painted a picture of a man who has always appeared uncomfortable with the spotlight. 

As an adult, in an interview with Britain's ITV, Charles revealed just how much he disliked the constant media attention.

"I'm not very good at being a performing monkey, really," he said. "I think I am quite a private person. I'm not prepared to just perform." 

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