Will Princess Diana's Brother — Charles, 9th Earl Spencer —Attend King Charles' Coronation?

Will Princess Diana's Brother — Charles, 9th Earl Spencer —Attend King Charles' Coronation?

As King Charles III's coronation plans take shape, Princess Diana's brother Charles, 9th Earl Spencer, revealed whether or not he'll be there.

Charles, 58, briefly spoke about the upcoming ceremony while appearing on Monday's episode of the Off Air… with Jane and Fi podcast. Diana's younger brother joined the show with his friend Rev. Richard Coles to promote their new podcast The Rabbit Hole Detectives, which debuted Wednesday.

Host Jane Garvey playfully asked Charles if he'd play a formal role in the May 6 crowning ceremony at Westminster Abbey given his peerage title.

charles spencer, princess diana, king charles
charles spencer, princess diana, king charles

Frederick M. Brown/Getty; Pool Photograph/Corbis/Corbis via Getty; Karwai Tang/WireImage

"I think we've never had an official role in it, just turned up like everyone else used to, when it was the hereditary peers and the House of Lords," the author and historian explained. "That's no longer the case. There is some old coronet knocking around somewhere, but I won't be wearing it soon, I don't think."

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Prince Charles, Prince of Wales and Camilla, Duchess of Cornwall sit during State Opening of Parliament in the House of Lords at the Palace of Westminster on May 18, 2016 in London, England. The State Opening of Parliament is the formal start of the parliamentary year. This year's Queen's Speech, setting out the government's agenda for the coming session, is expected to outline policy on prison reform, tuition fee rises and reveal the potential site of a UK spaceport.

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"Will you not be going?" Garvey pressed.

"I wouldn't have thought so — I think it's only about 2,000 people going," Charles replied, alluding to the widely reported guest count, scaled back from the 8,000 at Queen Elizabeth II's coronation in 1953.

On the same topic, the Off Air co-host continued, "Can I ask you, Charles, I imagine your feelings on that day might be quite mixed? Those of us with memories of your sister Diana, I think many of us...we will be thinking of her, and I hope that's not offensive, but she will be in our minds."

"I think that's very complimentary, actually," he replied. "Obviously, I think of Diana every day, in a different context."

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"Actually, the whole royal thing, I don't find it as interesting as a lot of people, you know? I just get on with my life," Charles said. "I look after what I have to look after at the estate, and I have a career, write books and such… People obviously assume that I care a lot about that side of things, but it's just a side part of my life."

Charles was a visible figure at Princess Diana's funeral in 1997, from walking behind her coffin with his young nephews Prince William and Prince Harry to delivering the eulogy.

Prince Charles
Prince Charles

JEFF J. MITCHELL/AFP/Getty From left: Prince Philip, Prince William, Charles Spencer, Prince Harry and Prince Charles walk behind Princess Diana's casket at her 1997 funeral

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More recently, the 9th Earl Spencer attended Queen Elizabeth's committal service following her death in September. The Queen was Charles' godmother, as his father John was an equerry to the monarch in the 1950s.

charles spencer, princess diana
charles spencer, princess diana

charles spencer/instagram

Before the somber service, Charles posted a photo of the royal cufflinks he planned to wear. The cufflinks featured Her Majesty's initials, E.R., as well as the Roman numeral "II" in the center.

"Wearing these at Windsor today, with great sadness and pride," he tweeted.