Prince William's Latest Concern About King Charles Revealed

Sources close to the Prince of Wales say he is worried about his "workaholic" father taking on too much amidst his cancer treatment.

Most royal admirers celebrated last week when King Charles III returned to his public-facing duties, but his heir was not as enthusiastic. According to a report by The Times, Prince William feels his father is taking on too much responsibility during his cancer treatment, calling him a "workaholic." At the same time, the Prince of Wales is trying to balance his workload with caring for his wife, Kate Middleton.

King Charles was hospitalized in January for a routine procedure, and a few weeks later he announced publicly that he had been diagnosed with an unnamed form of cancer. He received outpatient treatment and continued to work while suspending his public engagements and meetings. Last week, he made a triumphant comeback with a visit to The Macmillan Cancer Centre at University College Hospital in London. Since then, palace officials have announced a schedule of other engagements for the king, but the prince is among those worried it may be too much.

"He wants to make sure his father is balancing his recovery. He knows his dad loves work, but he does worry about him," an insider said. Sources close to Prince William pointed out that he had to process two cancer diagnoses close to him at nearly the same time, and he did so without taking a break from work. One friend noted that he attended several public engagements in the weeks before Middleton announced her cancer diagnosis, avoiding the topic and smiling through it all.

"I don't know how he managed to keep doing all that, knowing what he was going through, while the world was ridiculing and throwing s- at his wife while she was having chemotherapy," they said. "That speaks to his character, grit and determination to go out and do the job that is expected of him. He has taken most of it on the chin and got on with it."

The palace's official announcement last week said that the king's doctors were "sufficiently pleased with his progress" to allow some public engagements, but that this "will not be a full summer program," with only "a few engagements a week." For comparison, the king has been known to take on multiple engagements per day when he is healthy, but some question whether that would be possible at his age even if he weren't sick. An aide told The Times that the king's schedule for the summer "will be carefully calibrated with enough downtime so that it is not too draining."

"Some people might think he is trying to pedal twice as hard because he is conscious that time is running ahead of him, but he's like that any way," a friend said. "His downtime away from public life has been used productively, enabling him to keep thinking about the things he wants to get on with."

Sources noted that other royals have stepped up in the last few months – particularly Queen Camilla and Prince Edward. However, it's more complicated for Prince William as his wife has been diagnosed with cancer as well and is undergoing chemotherapy. The prince has reportedly prioritized his time with his wife and their three young children, but his schedule will fill up more in the next two months as he accompanies the king on some important engagements. He will, however, step back again starting in July while his children are on a break from school.

Friends said that Prince William has "been on good form" through the last few months, and that his "humor is always there," especially since Middleton announced her diagnosis in March and the secrecy was over. They said: "There is a huge sense of relief that the family have been given the privacy and peace they asked for. He continues to do his best to try to balance supporting his wife, family and father with his public duty as the Prince of Wales. But of course from the start of the year, the focus of his family has been at the forefront of his mind."