King Charles Had a 'Very Emotional' and 'Highly Unusual' Lunch With Kate Middleton as They Both Bravely Battle Cancer

King Charles and Kate Middleton are battling cancer at the same time, and experts believe His Majesty and the Princess of Wales are leaning on each other during this period. Shortly after Kate announced she will begin treatment for her condition, she had a private meeting with her father-in-law.

"It is highly unusual for just the two of them to sit down together like this," a source told an outlet. "The King had already been made aware that the woman he calls 'my beloved daughter-in-law' had cancer."

"They would have had lots to discuss and share because just weeks earlier the King had begun his course of treatment and dealt with announcing his diagnosis," they added.

On Friday, March 22, Kate returned to Instagram after months of fighting off conspiracy theories about her well-being.

"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."

The Princess of Wales continued: "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. 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."

Kate has been a member of the royal family for 12 years, and Charles was moved by her vulnerability after she updated the public on her health.

"The King left his lunch feeling very emotional," they noted. "They are very close and he thinks of Catherine as his daughter. There is no doubt there is a lot they can share and can use each other for support during their own deeply personal cancer battles."

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Shortly after the news broke, a rep for Charles released a statement.

The rep shared Charles is “so proud of Catherine for her courage in speaking as she did," adding the duo “remained in the closest contact with his beloved daughter-in-law throughout the past weeks."

Sources spoke to The Sun.