Prince William was reportedly not on good terms with Princess Diana when she died.

The late Princess of Wales was very close to her two sons Prince William and Prince Harry. However, according to a royal expert, 15-year-old Prince William was starting to rebel against his mother when the accident happened, which made the Duke of Cambridge all the more affected with his mom’s sudden death.

“Diana’s tragic death, in 1997, left her elder son wary and less certain of things,” Vicky Ward wrote for Vanity Fair in 2008. “The two had not been on great terms when Diana died, says American education consultant Tamara Rosenberg, who has known the Prince since his early teens when he was at Eton.”

Rosenborg told Ward that at the time, Prince William “was starting to chafe at being Mama’s boy.” The Duke of Cambridge was reportedly trying to be independent and then suddenly, the accident that killed Princess Diana happened. According to Rosenberg, Prince William never resolved that issue. Meanwhile, the duke’s relationship with his father, Prince Charles, is solid but distant.

A former courtier revealed that Prince William and Prince Harry have never forgotten that their father’s second wife, Camilla Parker Bowles, was their mom’s “bete noire for 15 years.”

Meanwhile, Prince William and Prince Harry both regretted their last phone call with Princess Diana. According to the two, they were in a hurry to end the call because they were playing with their cousins in Balmoral.

Prince William said that that up to this day, that call still sticks to his mind “quite heavily.” Meanwhile, Prince Harry also felt the same saying that it was “incredibly hard.”

“I’ll have to sort of deal with that for the rest of my life,” Prince Harry said. “How differently that conversation could have panned out if I’d had even the slightest inkling her life was going to be taken that night.”

Prince William and Prince Harry blamed the paparazzi for the accident after learning that they chased Princess Diana’s car in the tunnel. The Duke of Sussex admitted that one of the hardest things to come to terms was knowing that the people who chased Princess Diana’s vehicle were the same people who photographed her while dying on the backseat.

Princess Diana, Prince William, Prince Harry
Pictured: Princess Diana, Prince Harry, Prince William gather for the commemorations of VJ Day, 19 August 1995, in London. Getty Images/Johnny Eggitt/AFP