Prince William says year has been ‘brutal' amid King Charles' and Princess Kate's cancer diagnoses

Prince William said the past year has been “brutal” as his wife and father announced their diagnoses with cancer.

"It's been dreadful. It's probably been the hardest year in my life," William told NBC News' international partner, Sky News, at the end of a weeklong tour in Cape Town, South Africa, for the fourth annual Earthshot Prize.

King Charles III announced his cancer diagnosis in February following a procedure for benign prostate enlargement. During the procedure, "a separate issue of concern was noted," and further testing confirmed the presence of cancer, Buckingham Palace said at the time.

He resumed public duties as king in April after progress was made in his treatment.

In a video address released in March, Kate, the Princess of Wales, shared that she had been diagnosed with cancer and was undergoing "a course of preventative chemotherapy" following a period of widespread speculation about her health and whereabouts. She said the cancer was found during major abdominal surgery in January.

In September, Kate said she had completed chemotherapy treatment and would return to a light schedule of public engagements through the end of the year.

Neither Charles nor Kate has revealed what kind of cancer they were diagnosed with. Buckingham Palace said the king did not have prostate cancer.

Kate had largely been out of the public eye in the months after she announced her diagnosis, but state events and other ceremonies that members of the royal family usually attend have not stopped.

"Trying to get through everything else and keep everything on track has been really difficult," William, Prince of Wales, told Sky.

He said he is "so proud of his wife, I'm proud of my father," despite how difficult it has been, adding that Princess Kate is "amazing" and "doing well," according to Sky.

Sky noted that the prince seemed more relaxed than usual at his Earthshot Prize.

"It's interesting you say that, ’cause I couldn't be less relaxed this year," he told Sky. "So it's very interesting you're all seeing that. But it's more a case of just crack on and you've got to keep going. ... I enjoy my work, and I enjoy pacing myself and keeping sure that I have got time for my family, too." 

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