Last year, the Queen laid to rest her husband, Prince Philip, and as a result her childhood nickname fell out of use, as the Duke of Edinburgh was the last remaining royal to call her by this moniker.
READ: The subtle way the Queen honoured Prince Philip during the Platinum Jubilee
The poignant milestone was pointed out by Arthur Edwards in his moving piece about covering Philip's funeral in 2021. Sweetly, the fond moniker goes back to when the Queen was too young to be able to pronounce her own name, calling herself "Lilibet" instead.
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Her parents and grandparents soon took up the nickname, which the Queen's father, George VI, once quoted as saying: "Lilibet is my pride. Margaret is my joy."
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As a young royal, she would sign letters using this shortened form of Elizabeth.
The Queen and Prince Philip were married for 73 years
In one thank you note to her grandmother, Queen Mary, for example, she wrote: "Darling Granny. Thank you very much for the lovely doll's house. I do love it, and I have unpacked the dining room and the hall. Love from Lilibet xxx."
Although the name was affectionately used by her parents and her husband, no one else in the royal family calls the monarch "Lilibet".
However, the name is still in use as Prince Harry and Meghan Markle named their daughter Lilibet, in honour of Her Majesty. The young girl also has the middle name of Diana, in reference to the Duke's late mother.
And that's not to say that the Queen's children, grandchildren and great-grandchildren don't have other sweet names for her.
The monarch lost her husband last year
Her Majesty is called "Mummy" by Prince Charles, who referred to her as such during his speech for her 92nd birthday, causing her to react by rolling her eyes and laughing along with the audience.
Princes William and Harry were spotted cheering on "Granny" as her stunt double parachuted into the stadium at the 2012 Olympics, and the Duchess of Cambridge has also revealed that her oldest children, Prince George and Princess Charlotte, call their great-grandmother "Gan-Gan".
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