Long live the king? The royal family confronts mortality.

Autumn Brewington’s newsletter for The Post, Post Elizabeth, chronicled the transition from Queen Elizabeth II to King Charles III.

In 1952, Britain’s King George VI waved to his oldest child from a windy London airport tarmac as Princess Elizabeth set off on a multicountry tour initially planned for the king. A few months earlier, the king was treated for lung cancer by having his left lung removed, yet neither his heir nor his subjects knew the gravity of his condition. Less than a week after that goodbye, George died in his sleep.

Contrast that with Buckingham Palace’s announcement on Monday that George’s grandson, King Charles III, has cancer. The king has started unspecified treatment, the palace said in a statement, and the cancer is a “separate issue” from the recent disclosure of an enlarged prostate. As politicians posted platitudes, the media outlets reported that the king had informed his family and that Prince Harry, the younger son who opted out of royal life, would fly in from California. Prince William, heir to the throne, is expected to shoulder more public-facing responsibilities.

That’s about all we know. It’s not enough.

Charles “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,” the palace statement said. Similarly, the king announced last month that he was seeking treatment for a benign prostate condition “to encourage other men who may be experiencing symptoms to get checked in line with public health advice.”

Credit to Charles for these efforts at transparency. In our era of oversharing, Britain’s monarch is trying to balance respect for an individual’s privacy with the public’s right to know the health status of public figures. There are benefits: Searches for prostate information spiked on the National Health Service website after the king’s announcement, the Guardian reported.

The House of Windsor has traditionally prioritized privacy when it comes to royal health issues. Catherine, Princess of Wales, was hospitalized in 2012 for severe morning sickness early in her first pregnancy. Her condition — hyperemesis gravidarum, which causes severe nausea and vomiting — was disclosed. Last month, by comparison, the press team serving Prince William and his wife waited until a day after the princess had abdominal surgery to announce that Catherine had undergone an undisclosed procedure for a noncancerous diagnosis and that she would be in the hospital as long as two weeks. While the princess “appreciates the interest this statement will generate,” she prefers to keep her medical information private.

Cue the internet.

The royals have been inconsistent on health disclosures for years. In the spring of 2020, then-Prince Charles announced he had tested positive for the coronavirus and was isolating at home. Later that year, British tabloids reported that William had tested positive about the same time but said nothing to avoid causing public alarm. Positive coronavirus tests for Charles and his mother, Queen Elizabeth II, were announced in 2022. Yet, more recently, Buckingham Palace refused to comment on a biographer’s claim that Queen Elizabeth had cancer.

Private individuals have a stronger claim to privacy than the head of state or next in line. If you’re going to reveal that Britain’s sovereign has a cancer that was found during prostate treatment, it would be better to fill in the blanks on prognosis — both the type and stage of the disease. It’s all too easy to read urgency into Harry’s arrival in London on Tuesday. Perhaps, in a perfect world, there would be no speculation. But speculation fills all gaps in our royal-watching reality. Exhibit A: the recent claim on a Spanish television program that Catherine had been in a coma — a report that went viral before it was debunked. During Catherine’s 2012 hospitalization, Australian DJs prank-called the hospital where the princess was a patient and broadcast their conversation with a health worker. Days later, the nurse who transferred the call killed herself.

These are not easy decisions. There might always be a struggle with sharing vs. oversharing in discussions of personal health. The family’s willingness to disclose Charles’s cancer is a step in the right direction.

If there is a takeaway from what we know so far, it is the reminder that the Windsors of Britain are actual human beings. It’s easy to see the royal glam and miss the mortality behind the majesty. The extraordinary longevity of the late Elizabeth II and of her husband and her mother — combined, the three lived 296 years — perhaps lured their subjects, and their descendants, into thinking that those near the crown are somehow immune to time.

The truth demands the attention of a family who like to call themselves The Firm. Most of those representing the monarchy full time are older than 50. Britain’s “working royals” have dwindled to a small group, diminished by the public shaming of the king’s brother Prince Andrew (friend of sexual predator Jeffrey Epstein) and by the escape to California of Harry and his wife, Meghan, Duchess of Sussex.

The royal who took on the greatest number of public duties last year was Princess Anne, the king’s 73-year-old sister. The 76-year-old Camilla is also expected to shoulder more of the royal workload in the coming weeks. The notion that Charles would “slim down” the number of relatives on the public payroll seemed a modernizing idea 20 years ago. Now, the aging House of Windsor is facing a high-profile labor shortage — and is at a loss for words to share its problems with the public.