Last week, to wrap up a four-day state visit to Italy alongside wife Queen Camilla, King Charles III planted a tree. Waving his shovel after the job was done, he poignantly quipped, “Well, I do hope that I shall live long enough to see a little bit of growth in the tree.”
It’s impossible to ignore that Prince William—Charles’s eldest son and his heir—might, at 42, come face-to-face with the throne sooner than he expected.
When Charles became king in 2022, he was two months away from turning 74—at that age, the oldest person to take the British throne in history. Less than a year later, he was diagnosed with cancer, as was his daughter-in-law, Princess Catherine, nearly simultaneously.
The Princess of Wales announced in January that she is in remission; meanwhile, the king’s treatment continues, and on March 27 he was hospitalized after experiencing adverse side effects to said treatment. Though the scare was later called a “minor bump in the road,” it brought the reality of the situation back into focus.
“The people I’ve spoken to have said that the succession planning, as they call it, began even before Charles’ diagnosis,” royal author Tom Quinn tells Harper’s Bazaar. “I mean, he’s the oldest Prince of Wales to become king in history, so succession planning had begun before Charles came to the throne simply because of the age issue.”
Though Charles had potentially the longest apprenticeship of all time, Robert Hardman—author of the 2024 biography Charles III: New King. New Court. The Inside Story.—tells Bazaar that Charles had no formal preparation when it came to learning how to be a monarch. “It’s always a role where you learn by example,” Hardman says. As such, William isn’t necessarily undergoing training for the top job, but “they’re preparing William by giving him more of the sort of work that Charles would do,” Quinn says, adding that “Obviously, the cancer diagnosis has made everything more urgent.”
Christopher Andersen, author of many royal biographies including 2022’s The King: The Life of Charles III, says: “The palace is putting on a good front, but the situation, in reality, is still very fluid.” When it comes to the king, he adds, “It’s still touch-and-go.”
As Charles planted a tree in Italy, William, Kate, and their three kids, Prince George, 11, Princess Charlotte, 9, and Prince Louis, 6, enjoyed a ski holiday in the French Alps while the kids were on Easter break from school. It’s unknown how long the Waleses have before William becomes monarch, but for now, they are still building their own schedule of royal duties around the kids’ school schedule. “Their first priority is and has always been their children,” Andersen says, adding that “Kate and William really can’t allow dark thoughts to creep in at the moment.”
In a November 2024 interview, William candidly admitted that last year was “brutal” and the “hardest year in my life” watching both his wife and his father endure cancer diagnoses. “William has willingly been the visible face of the monarchy while all this drama is going on, but that doesn’t mean he’s not hurting,” Andersen says.
Of the future, “Officials and aides—people who work very closely with William and Kate and Charles—they’re all conscious that William might have to become king earlier than expected,” Quinn says. “Partly the cancer, partly simply [because Charles is] 76. He could go on another 10 years, he could go on for 20 years. But with the cancer diagnosis, it’s a wake-up call.” He adds that “Charles knows that he isn’t going to be king for that long.”
His condition, however, has not slowed the sovereign (and known workaholic) down. “Queen Camilla still worries that her husband is perhaps pushing himself too hard,” Andersen says. “Nobody really expected him to be an ideal patient. King Charles has always been very impatient and is accustomed to getting his way at all times. Anyone who thought he would obey his doctors and take it easy indefinitely doesn’t know the man.” Case in point? Less than two weeks after his hospitalization, he and Camilla were in Italy.
“The pace of this reign hasn’t changed since it started,” Hardman says. “Life is carrying on as it would’ve done if he hadn’t had the cancer. I think the best way of putting it is he’s living with cancer, rather than suffering from cancer.”
The night of his March 27 hospitalization, “He came back to Clarence House, he had dinner with Queen Camilla, and then he proceeded to do what he does every night, which is work,” royal biographer Sally Bedell Smith, who wrote the 2017 book Prince Charles: The Passions and Paradoxes of an Improbable Life, tells Bazaar. “That’s just an indication of how committed he is to doing his job with every ounce of energy he has.” Despite Charles’s energy, she adds, there is evidence of fatigue. “It’s safe to say that, even though he’s working as hard as he always has, that he doesn’t appear to be quite as robust as he once was,” she says. “But, then again, he’s getting older.”
Bedell Smith says discussions about succession and plans for after Charles’s reign ends are taking place—plans that Charles, like his mother before him, is actively involved with. With Charles’s parents, Queen Elizabeth II and Prince Philip, living to 96 and 99, respectively, many no doubt assumed that Charles, too, would probably live to be a nonagenarian. But cancer is a game-changing disease.
After waiting so long to take the throne, Charles “is determined to make his mark as king,” Bedell Smith says. “I would maintain that he made an extraordinary mark as Prince of Wales, and that’s a huge part of his legacy. But he doesn’t want that to be his only legacy. He wants to leave a legacy of his reign.” But, she adds, “I think he is probably measuring the rest of his time in years rather than decades.”
In the same vein, as far as William and Kate are concerned, “I think they’re very much aware that their time as Prince and Princess of Wales may be limited,” she says. “It’s probably safe to assume that they’re preparing for it sooner rather than later.”
