'Mischievous' Princess Margaret threw son's ex-girlfriend top-secret engagement party

Princess Margaret was known and loved for her rebellious spirit, which included organising a secret engagement celebration for her son David's ex-girlfriend.

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Susannah Constantine opened up about her relationship with Viscount Linley from 1983 to 1989 and recalled her relationship with the late Princess (whom she referred to as her "mother-in-law") in a new memoir, Ready for Absolutely Nothing. According to the MailOnline, the 60-year-old fashion guru said: "There was a deep sense of loyalty between us. Even after David and I separated, it never faded."

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What Not to Wear star Susannah revealed she didn't stay in contact with Margaret as she "felt it wasn’t appropriate when David got engaged to [his now ex-wife] Serena," The Times reported. However, she went on to marry Sten Bertelsen in 1995, and Queen Elizabeth II's sister made sure to celebrate her son's former girlfriend's new relationship with a special engagement dinner.

"In 1994, five years after I’d split from her son, she suddenly popped back up on my radar. Somehow or other she’d learned of my upcoming nuptials and wanted to host an engagement dinner for my fiance, Sten, and I at the ultra-discreet Blakes Hotel in South Kensington.

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Susannah Constantine married her husband Sten in 1995

"She knew she’d need to hold the dinner somewhere private because the Press would have had a field day had they found the princess serenading her son’s ex and her new beau," she explained.

Speaking of the "lovely" evening, Susannah - who shares children Cece, Esme, and Joe with Sten - said that the Princess was "mischievous" by "telling poor Sten how in love David and I had been."

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Margaret's son David dated Susannah in the 1980s

Susannah went on to joke that Margaret would have "made an excellent secret service agent" since not only David knew about the celebration until recently!

One example of the Countess of Snowdon's ability to keep news under wraps was when she announced her engagement to photographer Antony Armstrong-Jones following a low-key two-year relationship. The couple got married at Westminster Abbey on 6 May 1960, just over two months after they revealed their surprise engagement, in the first royal wedding to be broadcast on television.

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Margaret and Antony were parents to children David and Sarah

Margaret and Antony welcomed two children, David Armstrong-Jones and Lady Sarah Chatto during their 16-year marriage, but in 1978 they made history again by becoming the first royals to divorce since King Henry VIII in 1540.

Princess Margaret, who never remarried, sadly passed away in 2001 at the age of 71.

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