Queen Elizabeth's "Daredevil" Sister's Secrets Revealed by Her Close Friend

Lady Anne Glenconner, 90, wife of Colin Tennant, Lord Glenconner, has been a fixture in the royal circuit since she was young. Friends with Princess Margaret and Queen Elizabeth, she attended many high-profile events and has clinked champagne glasses with multiple members of the Royal Family for several decades. She has published a few books about her memorable life, the first, released a few years ago, dubbed Lady in Waiting, and now Whatever Next? Lessons from an Unexpected Life.

In it, she rehashes many memories related to the royals, but specifically her close friend, the younger sister of the Queen, for whom she was lady-in-waiting to. Lady Glenconner reveals what was like to travel with the controversial Princess on luxurious vessels, how she made people faint, Margaret's impressive drinking routine, and one particularly heart-stopping airplane stunt. Read on to learn more about Princess Margaret's secrets and her adventurous life.

Decades before Paris Hilton and Kim Kardashian, Princess Margaret was one of the world's first global celebrities. The daughter of King George VI and Queen Elizabeth The Queen Mother and the only sibling of Queen Elizabeth II, she was known for her glamorous lifestyle and ostensible romances. She is also one of the most talked about characters in the popular Netflix TV series, The Crown.

In one chapter of her book, Lady Anne Glenconner reminisces about a trip to Tuvalu. In an interview with The Times, she said: "The New Zealand navy lent Princess Margaret a frigate. We sat around having these rather terrible feasts and, from behind us, bare-bosomed ladies slapped down a sort of ghastly grey muck on our leaves – it was leaf service – which one had to eat."

According to Lady Glenconner, Princess Margaret could be as fearless as she was stubborn. She shares a story from a visit to Venezuela, where Margaret defied her advisors and took her life into her own hands. At the time, visitors wanted to take a flight in a small plane to enjoy views of Angel Falls waterfall — the world's tallest uninterrupted waterfall, with a height of 3,211 feet and a plunge of 2,647 feet. But plans were held up by the security officer who thought it would be too dangerous for the princess to board the flight. Princess Margaret initially accepted the recommendation but soon changed her mind.

"Suddenly there was a huge roar and up went the plane, with Princess Margaret on board," Lady Glenconner explains. "She'd sneaked away without telling us. We watched in horror, our hearts in our mouths, as the little aircraft whizzed over the falls." Princess Margaret's plane landed safely, but she had to face her unimpressed private secretary, who said very gravely. "Ma'am, you shouldn't have done that! You put us in an impossible position." He was proved right sooner than anybody could expect—two days later, the plane crashed and was destroyed. "I still feel slightly sick when I think about it," Lady Glenconner admits.

Lady Glenconner, whose role was often, as she puts it, to serve as a buffer between Princess Margaret and other people, shared more secrets about her friend's extravagant lifestyle. "She drank gin and tonic at lunchtime and whisky and water in the evening, so I'd check that someone had an eye on her glass to see if she needed another. She often did!," Lady Glenconner said.

She also added that the princess "valued friends who didn't want anything from her" and ones who weren't so "overwhelmed by her royal status that they couldn't act normally." "In Princess Margaret's presence, people occasionally stuttered, fell over (more than one lady sank so low in a curtsey that she collapsed) or even fainted," she explains.

In the book, she also talks about her upbringing and how her mother was lady-in-waiting to the Queen's mother, which is how she came to know both the Queen and Margaret. She even celebrated holidays with them at Sandringham.

She was also maid of honour at the Queen's coronation, where she was photographed and interviewed by the press with other girls. "We were a sort of harbinger of the girl bands," she said. "There'll never be another coronation like that, ever. It was really tip top."

What does she think about the King's plans for a much smaller soiree? "I think it has to be. And anyway, I'm so fond of King Charles but, you know, he's not young. The Queen was so beautiful, so glamorous, and look at the Duke of Edinburgh. He was to die for. People were madly in love with him. It was absolute perfection."

"I went to his wedding," Glenconner said about King Charles. "Both weddings, actually." She added that he will make a "great" king. "He's had long enough. He really minds about things and people and you can see it. And she's great. She's wonderful for him."

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As for The Crown, she maintains it is merely fiction. "One saw the moment when I was on, and Princess Margaret, and it bore no relation to the truth whatsoever. I don't watch it now. I couldn't. It would make me so angry, seeing people trashed like that. Well, not trashed, but not like them. It's fiction. I think it should say so clearly."