King Charles enjoys the jokes in the support cards

King Charles has been delighted by some of the 7,000 cards of support sent to him during his cancer treatment, including one that took a humorous point of view.

They enclosed a card with a picture of a dog wearing a protective cone that read: “At least you don't have to wear a cone!”

Other messages shared people's experiences with cancer and wished the king a “speedy recovery.”

The king described that he was “brought to tears” by the cards sent to him.

According to palace aides, despite the health concerns, there was “frequent laughter,” and the dog particularly entertained the king.

The names of the senders have not been revealed, but the company that made the card, Pigment, told the BBC it was one of their best-selling cards that had been personalized with the king's name – and they “hoped it would make the king smile.”

A selection of letters of support are placed in the red boxes containing the King's daily papers.

“I wanted to let you know that I am thinking of you as you face your diagnosis and treatment and I am sending prayers and all well wishes for your speedy recovery,” one well-wisher wrote.

Another said: “Lift your chin, open your chest, stay positive and don't let it get you down. Believe me, it works, but the main thing is family.”

A number of letters come from people facing their fears about cancer.

Rebecca Stead, from Macmillan Cancer Support, told BBC News: “Hearing the news that you have cancer is a big moment in anyone's life, and there is no right or wrong way to respond.

“Going through waves of different emotions is completely normal. But we know that many people will feel uncertain or anxious.”

She says this could relate to practical matters such as paying a mortgage or confusion about the treatment being offered, and urges people to seek advice.

The King's openness about having cancer has also been praised as it has helped remove taboos around the disease.

According to Macmillan, the King's public admission that he had cancer led to an increase in the number of people searching for information.

Macmillan's online information pages received 50,000 visits on the day the King's diagnosis was announced, 40% more than usual.

The king has retreated from public events but continues to work as head of state, including regular meetings with the prime minister.

The latest photos released by Buckingham Palace on Wednesday were taken before meeting Rishi Sunak.

When the Prime Minister said how good the king looked, he joked back: “It's all done with mirrors.”

Humor is often used by King, who was a huge fan of The Goons and participated in comedy shows at university. One contemporary student said: “I think he's actually quite shy, and it's a lot easier when you make people laugh.”

But in his current circumstances, the king was said to have been moved by hand-made cards from children, including the message: “Never give up. Be brave. Don't cross your limits. Get well soon.”