Prince William was reportedly “shaken to the core” by the dual cancer diagnoses of King Charles and his wife, Kate Middleton.

A new royal biography “The Windsor Legacy” claims the Prince of Wales, 43, wanted to take a step back from his royal duties in 2024, according to an excerpt obtained by the Daily Mail.

However, his request was denied by his sick father.

Written by biographer Robert Jobson, the book also notes that both William and Middleton, 43, “became more religious” as they struggled with the challenging year.

“Never known as a regular worshipper, William now attends church more frequently than in the past, though as privately as possible,” Jobson wrote.

Reps for Kensington Palace did not immediately respond to Page Six’s request for comment.

William previously gave a cancer update on his father and his wife during his October appearance on Eugene Levy’s “The Reluctant Traveler.”

After confirming his wife’s cancer-free status, calling it “great news,” the prince revealed that “things are good” regarding his father’s respective battle with cancer.

“Everything is progressing in the right way, which is all good news,” he added.

In the episode, William reflected on the toll Middleton’s diagnosis took on their family of five, saying, “You maybe think to yourself, ‘It won’t happen to us, we’ll be OK.”

“Because I think everyone has a positive outlook, you’ve got to be positive. But when it does happen to you, then it takes you into some pretty not great places,” William continued.

In September, Charles, 76, gave an update on his health, sharing that he’s “not [doing] too bad” himself.

Middleton finished her chemotherapy treatments in September 2024. In January, she announced that her cancer was in remission.

“I remain focused on recovery,” she wrote at the time in a lengthy statement. “As anyone who has experienced a cancer diagnosis will know, it takes time to adjust.”

The Princess of Wales has since resumed her royal duties.

Most recently, she and William celebrated their recent move to Forest Lodge in England’s Windsor Great Park with a private pub party earlier this month.

An insider told the US Sun that the family chose to relocate to put Middleton’s March 2024 cancer diagnosis behind them.

“Moving gives them an opportunity for a fresh start and a new chapter; an opportunity to leave some of the more unhappy memories behind,” a source told the Sun of the mom of three,