Prince William and King Charles Are 'Closer Than Ever' Amid Royal Health Crises

Prince William and King Charles have become each other's biggest support system as His Majesty and Kate Middleton battle cancer.

According to a source, the king and his heir are "closer than ever" as they juggle leading The Crown and the Princess of Wales' medical leave.

"If there was ever a green-eyed monster or a sense of rivalry between the two, that is a chapter of the past," the source told an outlet. "The King sees his son as a useful ally on family matters and increasingly in discharging the duties of nation and state."

"He very much wants to support his father," they added. "That isn’t something new, but of course, with everything the King is going through with his treatment, he will continue to support him as much as he can."

In March, Kate returned to Instagram to update the public on her health after months of speculation about her whereabouts.

"I wanted to take this opportunity to say thank you personally for all the wonderful messages of support and understanding whilst I've been recovering from surgery," Kate began. "It has been an incredibly tough couple of months for our entire family. In January, I underwent major abdominal surgery in London. At the time, it was thought that my condition was non-cancerous. The surgery was successful, however, tests after the operation found cancer had been present. My medical team therefore advised I should undergo preventive chemotherapy, and I am now in the early stages of that treatment."

"This of course comes as a huge shock, and William and I have been doing everything we can to process and manage this for our young family. It has taken my time for me to recover from my surgery," she continued. "Most importantly, it has taken us time to explain to George, Charlotte and Louis and to reassure them I am going to be OK. As I've said to them, I am well. Having William by my side is a great source of comfort, and the love and support and kindness that has been shown from so many of you. As a family, we need some time, space and privacy while I complete my treatment. My work has always brought me a deep sense of joy. I must focus on making a full recovery. At this time, I am also thinking of those whose lives have been affected by cancer. Please do not lose faith or hope. You are not alone."

Charles shared he was "so proud of Catherine for her courage in speaking as she did." The palace later said the monarch was in "closest contact with his beloved daughter-in-law."

Charles and Queen Camilla "will continue to offer their love and support to the whole family through this difficult time," the palace confirmed.

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Sources spoke to The Times.