Prince Harry celebrated his 36th birthday on Monday, and while this may not seem like a huge birthday for most people, it was undoubtedly a difficult one for the royal.

In turning 36, Harry is now the same age that his mother, the late Princess Diana, was when she was tragically killed in a car crash back in 1997. Harry as only 12 years-old when Diana passed away, and he has struggled to come to terms with her death ever since.

When Harry turned 18, he publicly vowed “to carry on the things that she didn’t quite finish.” Now living in Santa Barbara, California with his wife Meghan Markle, Harry appears to be trying to do just what he promised.

“I would call it destiny,” Omid Scobie, coauthor of the recent “Finding Freedom,” told Vanity Fair. “This is a man who said he wanted to continue his mother’s work. We’ve long mourned Diana’s place on the humanitarian landscape, and here we have Harry, who embodies her values and is willing to dedicate his life to them. He’s at an age now where he’s taken that baton and is able to run with it in a way that he would never have been able to do within the House of Windsor. That’s very powerful and exciting.”

Though living in California has undoubtedly been an adjustment for the British royal, Scobie said that he is “happier than ever” there.

“Here is a man who’s very content and happy with his marriage, his family life, and thriving within his professional life,” Scobie said. “This is the moment he can sit back and think, ‘I made it.’ He has found his happiness.”

Royal author Ingrid Seward agreed with this sentiment.

“He can celebrate his birthday on a high,” Seward said. “He’s embracing his new life and everything is an adventure right now. He has moved on very quickly, and I don’t think he misses his old life at all.”

Diana’s former private secretary Patrick Jephson, however, had more cautionary words for Harry. He pointed out that as someone who has left the United Kingdom behind and gone Hollywood with a massive Netflix deal, Harry is being viewed very differently these days.

“Having reached the same age at which his mother died, Harry has arrived at a point of no return,” Jephson said. “A life on the American public stage is now his destiny unless he decisively turns away from it. The time to do so is fast running out. We must hope—as Princess Diana surely would—that he has weighed his options wisely.”