Kate Middleton and Prince William’s daughter is known to the world as Princess Charlotte — but do you know her full name? The Duke and Duchess of Cambridge welcomed their second royal baby on May 2, 2015, at London’s St Mary’s Hospital. Two days later, Kate and William announced their little girl’s full name… Charlotte Elizabeth Diana. So how did Kate and William — who are also parents to a son Prince George! — choose Charlotte’s moniker?

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Kate, William, George and Charlotte in June 2016. (Photo Credit: Getty Images)

The royal baby’s first name is a nod to two of the couple’s family members. Charlotte — which dates back to the 18th century and has a French origin meaning “free man” or “petite” — is the female diminutive of William’s father’s moniker, Prince Charles. Kate also honored her younger sister, Pippa Middleton, with her daughter’s name as Pippa’s full moniker is Philippa Charlotte.

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Charlotte’s first middle name, Elizabeth, pays tribute to William’s great-grandmother, Queen Elizabeth The Queen Mother, and grandmother, Queen Elizabeth II. But it’s the little royal’s second middle name, Diana, that has an especially touching meaning to her dad, William.

Diana, of course, is a nod to William and Prince Harry’s late mother, Princess Diana. “It’s William’s way of honoring his mother’s memory. A way of making sure Diana’s legacy lives on. This way she will never be forgotten,” Diana’s close friend Simone Simmons told Vanity Fair in a previous interview.

Though many royal fans hoped Kate and William would give their daughter Diana as a first name, writer Richard Kay believes having the moniker as the baby’s middle name was the right choice. “Had it been the first name, I think it would have been terrible for the child,” he told VF.

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“There would have been constant comparisons with Diana, and William wouldn’t have wanted that,” Kay continued. “This way it’s a tribute to his mother and a way of ensuring Diana is always remembered.”

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