Sarah Ferguson's moving message to King Charles about shared battles with cancer

Sarah Ferguson has delivered a touching message to the King about the royal's shared cancer battles.

The Duchess of York said Charles is “very dear” to her in a social media post about the first event she attended since revealing her malignant melanoma diagnosis and since hearing the news that the monarch is being treated for an undisclosed form of cancer.

Writing on Instagram on Saturday, the 64-year-old said: “His Majesty is very dear to me and I think I speak for everyone when I say he is in my thoughts and prayers.”

The words appeared alongside a photo of her giving a speech at the Cancer Alliance's Hope and Help Luncheon in Palm Beach, Florida, on Wednesday.

A source told online mail The Duchess and the King have bonded in letters through their battles with cancer.

They said: “The King and Sarah love each other very much and have now bonded over their respective cancer diagnoses through an exchange of letters. “Cancer is a malignant disease that affects many people and their families and it is clear that additional support from loved ones and the wider cancer community can be of great help.”

It comes after Ferguson, mother of Princesses Beatrice and Eugenie, took to Instagram in late January to break her silence for the first time since her diagnosis last month. She said she was in “shock,” but added that she was still in “good spirits,” as she thanked those who supported her and praised the doctors who treated her.

The Duke of York's ex-wife was then photographed leaving King Edward VII Hospital in London on January 25 in what was the first photograph of the Duchess since making her health announcement. After visiting her dermatologist at Marylebone hospital, Ferguson told people outside: “I'm fine, thank you.”

A spokesman had said it was undergoing further investigation to ensure the disease had been detected in the early stages.

The news emerged less than a year after she underwent a mastectomy and reconstructive surgery in London for breast cancer, and then recovered at the Mayrlife Clinic in Austria.

Ferguson also wrote in her most recent social media post about the importance of raising funds to support those fighting cancer, taking the opportunity to raise awareness for those who may be struggling financially or emotionally following a diagnosis.

She said: “It seemed like an opportune time to help raise funds to support other people facing cancer diagnoses and who may be experiencing financial or emotional difficulties due to a health emergency. “It was both healing and inspiring to meet so many incredible women, who do so much for others through their work with Cancer Alliance.”

The King announced his own cancer diagnosis on Monday, hoping to raise awareness about the disease. A statement issued by Buckingham Palace said: “Her Majesty has decided to share her diagnosis to avoid speculation and in the hope that she can help public understanding of all those around the world affected by cancer.”

The 75-year-old monarch revealed his health news, discovered during an operation for a benign enlargement of the prostate, before flying with Queen Camilla to Sandringham the next day, where he will rest after the start of treatment.

On Wednesday night he issued a statement to mark the 50th anniversary of the independence of the former British colony of Grenada. Charles apologized for not being able to visit the Caribbean island, referring to Grenada's national dish, a stew known as “Oil Down.”

The recent cancer diagnoses of both the king and the duchess come as the Princess of Wales is recovering after being discharged from hospital late last month, having undergone planned and successful abdominal surgery.

Both Charles and Catherine have stayed away from public engagements while they recover, and the princess will return to royal duties after Easter.