When Princess Diana joined the royal family, she may not have been completely aware of the “machine she was in,” according to a close friend.

Dr. James Colthurst, then a medical student, first encountered Diana when he was called to examine her injured ankle when she was on a skiing vacation in Val Claret, France, when she was 17 years old.

“I felt, when she joined the Royal family, she may not have been fully aware of the machine she was in,” Colthurst wrote in The Telegraph, recalling the pressure Diana experienced as a 20-year-old. “The Firm, for its part, was unaccustomed to having a superstar in its midst, and I don’t think they knew how to cope with the enormous amount of publicity she generated.”

He went on to develop a strong relationship with Diana, whom he described as ‘fun,’ ‘bright,’ and’mischievous,’ and was the intermediary who transported recordings of the late royal’s confessions to author Andrew Morton for his blockbuster book of revelations, Diana: Her True Story.

He also reminisced on the events leading up to her wedding to Charles. Clarence House had not given Diana a detailed briefing on what to anticipate after the wedding.

He went on to add that he doesn’t think anybody was ‘prepared’ for how famous she would become in her own right, saying that there was ‘jealousy’ within Prince Charles’ staff as her worldwide popularity grew.

“She didn’t have a big support team at the Palace herself: she was just trying to do her best. When she did what she thought was right, it was well received by the public but not always by the Firm,” Colthurst explained.

During the tumultuous years of her marriage, he claimed to have received between eight and ten phone calls each day from her.

The late Princess of Wales seemed to be ‘happy’ in her last months and wasn’t in a ‘bad place,’ having recently returned from a summer vacation.

But, according to Dr. Colthurst, it was her dedication to issues dear to her heart, such as assisting those living with HIV, that got her through the tough times.

He recounted one of his final recollections of his close buddy, describing how she laughed ‘almost uncontrollably’ over the phone when someone gave her a very odd poetry etched on a silver tablet.

Diana died in Paris in August 1997, at the age of 36.

The remarks came after Prince Harry, 36, was reconciled with his brother, Prince William, 39, at Kensington Palace on Thursday, where they presented a monument of their beloved late mother on what would have been her 60th birthday, following a difficult 18 months for their own relationship.