For the Prince of Wales, the blows have come swiftly one after the other. First his father, King Charles, revealed that he had been diagnosed with cancer, and then came the news from doctors that his wife, Catherine, the Princess of Wales, also has cancer.

The stress on the heir to the throne will be considerable. Not only must he support his wife and father, he must also shepherd his young children through a family medical crisis in the glare of global media coverage. And he must shoulder much of the responsibility of steering the monarchy through challenging months ahead.

In her video statement released on Friday, Kate acknowledged her husband’s role in her recovery from surgery and treatment for cancer. “Having William by my side is a great source of comfort and reassurance,” she said.

Immediately after Kate’s abdominal surgery in January, William took time off to support his family. But on 6 February, he returned to royal duties as Kate recuperated at home in Windsor.

Three weeks later, he suddenly pulled out of attending a memorial service for his late godfather, King Constantine of Greece, citing unspecified “personal reasons”. That triggered frenzied speculation on social media. It is thought that Kate’s diagnosis landed about this time.

King Charles also missed the service, leaving Queen Camilla and Prince Andrew to lead the royal party.

Now Kate is undergoing chemotherapy, it is unlikely she will perform any official duties for the foreseeable future. The king has resumed limited engagements in the past month, such as an audience with Rishi Sunak and a privy council meeting, but is not expected to travel or undertake arduous engagements.

William’s priority over the next few weeks will be his family. The prince is able to take as much time as he needs without financial worries or fear of losing his job. Many spouses or partners in a similar position have to make hard choices.

“Balancing working and caring” for someone with cancer “can be difficult”, says the charity Macmillan Cancer Support. It advises trying to find a “balance between the support you want to give and what you are able to do”, and talking to employers about possible flexible working arrangements.

Many people depend on the support – practical and emotional – of close relatives. Not for the first time, William may be reflecting on the breakdown in the once close relationship with his brother Harry, now living thousands of miles away and largely estranged from his family.

While many families pull together in a crisis, and strengthen mutual bonds, this seems unlikely for the royals.