Prince William and Kate Middleton.

With Kate Middleton and King Charles both undergoing cancer treatment, Prince William must balance family matters with an elevated leadership role within the monarchy.

“Whether you’re a prince or a pauper, no one would expect anything like this with his father and his wife both being treated for cancer,” a royal insider tells PEOPLE exclusively in this week’s cover story. “William is digging deep.”

The Prince of Wales, 41, has resumed public duties after taking time off to spend time with his wife and their three children — Prince George, 10, Princess Charlotte, 9, and Prince Louis, 6 — immediately following the news of her cancer diagnosis, publicly announced on March 22. However, his primary focus remains steadfastly on supporting Princess Kate, 42.

“For William, everything hinges on Kate’s well-being,” says royal biographer Ingrid Seward, author of My Mother and I.

From left: Prince George, Kate Middleton, Prince Louis, Princess Charlotte and Prince William at Trooping the Colour on June 17, 2023.

CHRIS JACKSON/GETTY

Throughout their 13-year marriage, the Prince and Princess of Wales have prioritized private time with George, Charlotte and Louis, routinely clearing their public schedules during school breaks and taking part in school drop-offs and pick-ups rather than always leaving the task to a nanny. Now, their family-first manta is more important than ever.

“William is prioritizing giving her all the time she needs to get better and the support, particularly to the children,” says a close source.

William’s Private Struggle.

Adds longtime royal biographer Robert Lacey, “From what we know of their personal lives, for William and Kate, spending time with their children is the most precious and enjoyable thing they can do.”

It was just one year ago at King Charles and Queen Camilla’s coronation on May 6, 2023, that Prince William, as heir to the throne, knelt before his father and recited a vow known as the Homage of Royal Blood. However, he likely had no idea how soon he would need to step into his royal destiny and become the face of the royal family amid King Charles and Kate’s cancer news.

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Prince William visits St. Michael’s Church of England School on April 25, 2024.

SAMIR HUSSEIN/WIREIMAGE

Despite the shock, the Prince of Wales has continued to bring cheer to his royal engagements — like telling one of Princess Charlotte’s favorite jokes during his April 25 school visit focused on mental health initiatives — and reassure the public. When asked by a well-wisher about Princess Kate and the children following his visit to the charity James’ Place Newcastle on April 30, he said, “We’re all doing well, thank you.”

“The double illness has placed enormous pressure on William, both as a parent and inheritor of the family business,” says Lacey. “It has brought all kinds of challenges. He [has handled] it with calmness and lack of drama.”