Under rules that are more than a century old, any child or grandchild of the monarch can get royal titles.

While Harry’s grandmother reigned, the Mountbatten-Windsor children, Archie Harrison, 3, and Lilibet “Lili” Diana, 1, were too far down the line of succession to be automatically entitled to royal titles. (The queen, namesake of little Lilibet, had the power to change that but did not, much to the chagrin of Harry and Meghan fans.)

Under King Charles III, Archie and Lilibet as his grandchildren traditionally would be given new honorifics — but it is not clear whether they have gotten them yet.

“I would expect the situation to be clarified. It hasn’t been,” royal commentator Richard Fitzwilliams said Sunday.

Queen Elizabeth II’s line of succession, visualized

In a list of those in line to succeed the monarch published by Buckingham Palace, Archie and Lilibet — respectively sixth and seventh in line to the throne — were referred to as “Master” and “Miss,” not “Prince” and “Princess.”

This fueled speculation that Charles, who has famously said he wants the ranks of the monarchy to be “slimmed down” around a core set of full-time working royals, might break with precedent and decline to offer his grandchildren royal titles. The palace did not immediately respond Sunday to a request for comment from The Washington Post.

The question of Archie and Lilibet’s status took on new urgency last year when the couple said in an interview with Oprah Winfrey that the royal family treated their firstborn child, Archie, differently, including by denying him the title of prince — a move Meghan, whose mother is Black, suggested was driven by institutional racism within the monarchy.

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In 1917, King George V, Harry’s great-great-grandfather, issued a legal document known as Letters Patent laying out which royals were entitled to the title of prince or princess and of HRH, his or her royal highness, and the regal trappings that come with them, which can include financial compensation and patronages.

Harry and Meghan gave up their own HRH titles as part of an agreement with the royal family when they retreated into more private lives and moved to North America. (As The Post has reported, the couple and their children have moved into a $14.7 million home in Montecito, Calif.)

“The grandchildren of the sons of any such Sovereign in the direct male line (save only the eldest living son of the eldest son of the Prince of Wales) shall have and enjoy in all occasions the style and title enjoyed by the children of Dukes of these Our Realms,” the 1917 document reads.

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This means that while Elizabeth reigned, of all her great-grandchildren, only Prince William’s eldest son, Prince George, was entitled to be called his royal highness. However, she issued a patent to allow George’s siblings, Prince Louis and Princess Charlotte, to have HRH titles.

With the accession of Charles to the throne, Archie and Lilibet “should’ve been offered [royal titles],” Fitzwilliams said.

In her interview with Winfrey, Meghan said that while she was pregnant with Archie, she learned that Buckingham Palace “didn’t want him to be a prince or a princess” and that “he wasn’t going to receive security.”

In the face of extreme media scrutiny of her and her family, Meghan said, she was concerned her son would be less safe if he didn’t enjoy the full protection she felt came from a royal title. She also said she and Harry didn’t make the decision not to give Archie the title of prince, as some media reports at the time had suggested.

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When asked why she thought the royal family didn’t make Archie a prince, Meghan said conversations were happening “in tandem” about how Archie wouldn’t be given a title and about “how dark his skin might be when he’s born.”

“The implication was that they weren’t offered titles and that was linked to racism,” Fitzwilliams said. “That was extremely damaging.”

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Not all royals choose to take a title, and it’s not clear whether Harry and Meghan will want their children to have them even if they are offered, Fitzwilliams said.

Princess Anne, the daughter of Elizabeth, chose not to give her children, Peter and Zara, HRH titles. She spoke about her decision in a 2020 interview with Vanity Fair. “I think it was probably easier for them, and I think most people would argue that there are downsides to having titles,” she said. “So I think that was probably the right thing to do.”

While there are many advantages to being a titled member of the royal family, a major downside is the lack of privacy that comes with an elevated status in the eyes of the press and the public. “On the other hand, if Harry and Meghan are desperately sensitive about this issue, as it appeared on Oprah they were, it’s very important of course [that Archie and Lilibet] be offered them, because that’s the 1917 edict,” Fitzwilliams said.

If they weren’t offered titles, “obviously it would be seen as a deep snub,” he added. “If they were and if they decided not to take them, that’s an individual choice.”

William Booth, Karla Adam and Jennifer Hassan contributed to this report.