On Feb. 10, five days after Buckingham Palace announced the monarch's diagnosis, the 75-year-old released a personal letter to the public.
"I would like to express my most heartfelt thanks for the many messages of support and good wishes I have received in recent days," the King wrote, as seen in a post shared on the Royal family's Instagram page, which also featured a 2023 photo of the monarch greeting well-wishers. "As all those who have been affected by cancer will know, such kind thoughts are the greatest comfort and encouragement."
The monarch continued, "It is equally heartening to hear how sharing my own diagnosis has helped promote public understanding and shine a light on the work of all those organizations which support cancer patients and their families across the UK and wider world. My lifelong admiration for their tireless care and dedication is all the greater as a result of my own personal experience."
He signed his letter, "Charles R"—his Royal cypher, which stands for "Rex," the Latin word for "king."
His letter was printed on letterhead that read "Sandringham House," the name of the monarch's country home in Norfolk, England.
The King—who has resided at Clarence House in London for years even before he ascended to the throne in 2022 following his mother Queen Elizabeth II's death—flew to Sandringham by helicopter with wife Queen Camilla Feb. 6.
The two had also visited their country estate Feb. 4 to attend a Sunday church service. On Feb. 5, about a week after the King was released from hospital after undergoing a procedure to treat an enlarged prostate, Buckingham Palace announced the monarch has been diagnosed with an unnamed form of cancer . (The Palace told NBC News it is not prostate cancer.)
"During The King's recent hospital procedure for benign prostate enlargement, a separate issue of concern was noted," their statement read. "Subsequent diagnostic tests have identified a form of cancer. His Majesty has today commenced a schedule of regular treatments, during which time he has been advised by doctors to postpone public-facing duties."
Hours before Charles and Camilla departed for Sandringham for their current stay, the monarch met with his son Prince Harry, who had traveled to London from California—where he lives with wife Meghan Markle and their kids Prince Archie, 4, and Princess Lilibet, 2. After a brief visit, the Duke of Sussex jetted back to the United States, where he presented an award at the 2024 NFL Honors event in Las Vegas.
"I'd like to take this opportunity to say thank you also for the kind messages of support for Catherine and for my father, especially in recent days," the Prince of Wales shared during the London's Air Ambulance Charity Gala Dinner on Dec. 7. "It means a great deal to us all."
A day later, Camilla offered an update on the King's wellbeing during a public appearance at a charity concert at England's Salisbury Cathedral. Per The Telegraph, she told an air ambulance worker, "He is doing extremely well under the circumstances. He is very touched by all of the letters and messages the public have been sending from everywhere. That's very cheering."
Read on for more news from royal families around the world this year:
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