Prince William likely to step up amid King Charles III's cancer diagnosis, experts say

Prince William is likely to do some heavy lifting in the British royal family amid King Charles III's cancer diagnosis.

The Prince of Wales, who is first in line to the throne, has already taken on more responsibilities after father Charles sought treatment for an enlarged prostate last month and wife Princess Kate postponed her appearances at royal events until Easter due to recovery for an abdominal surgery.

"During The King's recent hospital procedure for benign prostate enlargement, a separate issue of concern was noted. Subsequent diagnostic tests have identified a form of cancer," Buckingham Palace said in a statement on Monday.

The palace also informed that His Majesty was "advised by doctors to postpone public-facing duties" amid his treatment.

Prince William will preside over investiture ceremony, a charity dinner this week

With both Charles and Kate out of the public eye, experts predict William will have added responsibilities in his role within the royal family.

"I also just feel like the pressure on William has never been greater because his wife is not able to participate, he has three children he's kind of helping look after, as he should, and then now, he has to kind of carry the weight (of father King Charles)," royal observer Rachel Bowie, who co-hosts the popular "Royally Obsessed" podcast, told USA TODAY.

William, who'd taken time off to look after the couple's three children, is due to preside over an investiture ceremony at Buckingham Palace and a charity dinner on Wednesday.

Though the palace's candor about royal health issues was a change from typical protocol, the kind of cancer Charles has and its severity has not been disclosed.

The monarchy's next large-scale event is Commonwealth Day on March 11, which is typically marked by a service at Westminster Abbey. In previous years, Charles and the late Queen Elizabeth II have repledged their commitments to the British Commonwealth nations.

It's unclear if the service will continue and to what capacity.

King Charles' cancer diagnosis:How we talk about it matters — here's why

Prince William is first in the line of succession if King Charles dies

As the first in line to the throne, William is generally regarded as the second in command.

"We're set to see William return to royal duties on Wednesday, but I do feel like when you look at the monarchy right now … just with the prostate treatment that Charles was undergoing when everything seemed fine, and then you have Kate out of commission, I think it really does make you think about just how slim the monarchy feels," Bowie said on Monday.

Charles took the throne intending to preside over a slimmed-down monarchy with fewer senior royals carrying out ceremonial public duties. But with Charles and Kate both temporarily sidelined, Prince Harry self-exiled to California and Prince Andrew largely banished from view because of his friendship with sex offender Jeffrey Epstein, the royal firm risks becoming severely overstretched.

At Charles' coronation in May, the Prince of Wales swore his loyalty to his father in a ceremony known as "The Homage of Royal Blood."

William kneeled before his father, placing his hands in between Charles' hands as he said, "I, William, Prince of Wales, pledge my loyalty to you and faith and truth I will bear unto you, as your liege man of life and limb. So help me God."

The ceremonious vow took place shortly after Charles' crowning and "The Homage of The Church of England," which was carried out by the Archbishop of Canterbury.

What we know so far:King Charles diagnosed after hospitalization for prostate procedure

William's children — Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5 — are next in the line of succession, followed by Prince Harry and his children, Archie, 4, and Lilibet, 2.

William has already stepped up since Charles' ascension to the throne after the death of the late Queen Elizabeth II by being more active in charities related to the environment, a cause his father was very passionate about before becoming king.

Bowie said the king's cancer diagnosis makes her "worried" as Harry prepares to travel to Britain, calling it a "royal rollercoaster."

How long has Charles been king?

Though he legally became king when his mother died, Charles has officially been king of the United Kingdom of Great Britain and Northern Ireland for less than a year, since his coronation in May after succeeding Elizabeth, Britain's longest-serving monarch.

He was the oldest monarch to be crowned in British history last spring after serving for seven decades as the monarch-in-waiting after he was made the heir apparent at 3 years old following the death of his grandfather, King George VI.

As the 41st British monarch since William the Conqueror in 1066, Elizabeth was the symbol of stability as Britain and its near 1,000-year-old monarchy sailed through roiling storms of history. 

Cold life-expectancy calculations suggest Charles' reign will not come close to matching his mother's in years. He's more likely to echo the experience of one of his ancestors, Edward VII, who waited almost 60 years to succeed his mother Queen Victoria in 1901, and then reigned for only nine years. 

Christopher Andersen, author of multiple royal biographies thinks Charles could still enjoy a longish reign given his parents' longevity. (His father, Philip, died just short of his 100th birthday.)

England's shortest reign was held by Lady Jane Grey, known as the "nine-day queen," who in 1553 ascended the throne at 16 years old. Nine days later, Mary Tudor claimed the throne. In February 1554, Lady Jane and her husband were beheaded at the Tower of London.

King Charles has cancerand we don’t know what kind. How we talk about it matters.

Prince William took over King Charles' title as the Prince of Wales

In a national address to the nation in September 2022, the king paid tribute to his mother Elizabeth II and named his eldest son William the Prince of Wales, a move signifying his shifting rank in the family.

With that, the former Kate Middleton became the Princess of Wales, the first to hold that title since the death of William's mother, the late Princess Diana, in 1997. In fact, she is one of only three princesses to be known as Princess of Wales since 1901.

"Today, I am proud to create him Prince of Wales, Tywysog Cymru, the country whose title I have been so greatly privileged to bear during so much of my life and duty," the king said in the pre-recorded speech. "With Catherine beside him, our new Prince and Princess of Wales will, I know, continue to inspire and lead our national conversations, helping to bring the marginal to the center ground where vital help can be given."

The royal family tree:A guide to the British monarchy and succession

Contributing: KiMi Robinson, Nicole Fallert, Maria Puente, USA TODAY; Danica Kirka, Sylvia Hui and Jill Lawless, The Associated Press