Cancer in the Royal Family: Kate Middleton, King Charles and Sarah Ferguson Announce Diagnoses in Same Year

In an unprecedented crisis, three members of the royal family have shared their cancer diagnoses.

After Kate Middleton's recent shocking health update, the Princess of Wales has become the third member of the royal family to be diagnosed with cancer in as many months.

On Friday, Kate, 42, announced her cancer diagnosis in a video statement shared by Buckingham Palace. She explained that she was diagnosed after her major abdominal surgery in January. Although the mother of three did not reveal what kind of cancer she's battling, she shared that she's currently undergoing "preventative chemotherapy" and is "now in the early stages of that treatment."

Kate said the news of the cancer diagnosis came as a "huge shock" to the royal family. She explained that she and her husband, Prince William, endeavored to manage the situation privately for the sake of their young children -- Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5. 

"As you can imagine, this has taken time. It has taken me time to recover from major surgery in order to start my treatment," she shared in the video. "But, most importantly, it has taken us time to explain everything to George, Charlotte and Louie in a way that's appropriate for them and to reassure them that I'm going to be okay. As I said to them, I am well, and getting stronger every day by focusing on the things that will help me heal. In my mind, body and spirits. Having William by my side is a great source of comfort."

The mother of three's announcement came a month after Buckingham Palace's February reveal that King Charles III, 75, had been diagnosed with cancer after an unrelated procedure for an enlarged prostate. The palace has not clarified what kind of cancer Charles has or what stage. 

"The King is grateful to his medical team for their swift intervention, which was made possible thanks to his recent hospital procedure," the palace shared in a statement. "He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible. His Majesty has chosen to share his diagnosis to prevent speculation and in the hope it may assist public understanding for all those around the world who are affected by cancer."

In the wake of his diagnosis, William took over many of his father's official duties as Charles' duties were scaled back for cancer treatment. Prince Harry also made a 24-hour visit to see his dad.

After Kate's announcement, a Buckingham Palace spokesperson told ET that Charles, who visited his daughter-in-law at the London Clinic where she had surgery before his own procedure, is "so proud of Catherine for her courage in speaking as she did."

Following their time in hospital together, Charles has "remained in the closest contact with his beloved daughter-in-law throughout the past weeks, and both royals "will continue to offer their love and support to the whole family through this difficult time."

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In January, a representative for Sarah Ferguson, the Duchess of York, 64, shared that she had been diagnosed with malignant melanoma six months after she underwent surgery for breast cancer

Ferguson's diagnosis came after a series of moles were removed from her body when she underwent reconstructive surgery following her mastectomy. 

"She is undergoing further investigations to ensure that this has been caught in the early stages. Clearly, another diagnosis so soon after treatment for breast cancer has been distressing but the Duchess remains in good spirits," the rep said in a statement.  

According to the rep, the duchess wanted to extend her gratitude to the medical professionals and encourage everyone to have their moles checked. Ferguson is being treated by Dr. Andrew Furness, consultant medical oncologist at the Royal Marsden Hospital in London, and Catherine Borysiewicz, consultant dermatologist at the King Edward VII Hospital in London, and has been recuperating at the MAYRLIFE clinic in Austria.

"The duchess wants to thank the entire medical team which has supported her, particularly her dermatologist whose vigilance ensured the illness was detected when it was," the rep continued. "She believes her experience underlines the importance of checking the size, shape, color and texture and emergence of new moles that can be a sign of melanoma."

This is not the first time cancer has affected the royal family -- Queen Elizabeth II's father had lung cancer before his death at 56, making Elizabeth queen.

Calling it "astonishing" to have three royal family members sharing cancer diagnoses consecutively, royal expert Katie Nicholl tells ET that the public still doesn't know when Charles "will return to work."

"We understand that Catherine has been able to do some work from home ... but as she said in that message, the focus has to remain on her recovery," Nicholl notes. "So we don't know when she's going to be back to work. So the monarchy is looking pretty thin on the ground. It was always Charles' wish to have a slimmed-down, scaled-back monarchy, but this is looking pretty skeletal."

On Jan. 29, the palace announced Kate would not be returning to official royal duties until after Easter, which takes place on March 31 this year.

Queen Camilla shared a health update on Feb. 9, saying Charles was "extremely well under the circumstances." The palace also shared a statement, confirming that Kate was "making good progress" while also expressing the couple's sincerest thanks for the outpouring of support.

Nicholl says that with two senior members of the royal family "out of action," there's "a huge pressure on [Queen Camilla]."

"We've seen Queen Camilla, she's 76, carrying out a really busy schedule of engagement, standing in for the king at the Commonwealth Day service. And there's also a huge amount of pressure on Prince William to step up to the plate, as well," Nicholl says.

She recalls the late Queen Elizabeth's motto, "I have to be seen to be believed," and says that the mantra "is as true now as it was then."

"The monarchy constantly evolves [and] it's been through worse than this," Nicholl declares. "The monarchy constantly evolves, and over the years, it has been very, very, very challenged. This is a major obstacle and the hope is we're going to see the king return to work in due course and Catherine as well."

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