Princess Charlotte was born Charlotte Elizabeth Diana on 2 May 2015, and her full name is chock-full of sweet references to other members of the Royal Family.
Starting with the obvious, Charlotte's second name Elizabeth is a nod to her late great-grandmother Queen Elizabeth II, while her third name Diana was chosen to honour her late grandmother Princess Diana.
But one royal reference in Charlotte's name you may not have realised was there is actually hiding in plain sight: her first name is the feminine version of Charles, after her grandfather King Charles III, as pointed out by the Mirror.
However, the name Charlotte also has a sweet significance for her mum Princess Kate, whose younger sister Pippa Middleton has Charlotte as a middle name.
At the time of Charlotte's birth, a friend of the late Princess of Wales' told Vanity Fair: "Diana would be over the moon. It's William's way of honouring his mother's memory. A way of making sure Diana's legacy lives on. This way she will never be forgotten. When Diana was alive, William promised her when he was King [that] Diana would have her HRH restored. This is his way of doing it."
Speaking on a documentary earlier this year, royal expert Richard Kay praised Prince William and Kate for not calling their daughter Diana as her first name.
"I think [Prince William] very wisely decided not to give Charlotte his mother's name as her first name," Richard said. "Everything she did and said would have been compared with her."
He added: "By giving Diana as the middle name, it means Diana is still there."
Despite having a very regal name on her passport, the little princess has a pretty normal one at school: Charlotte Wales (formerly Charlotte Cambridge).
Like many other nine-year-olds, she's also known by some sweet nicknames, including Mignonette, poppet, and Lottie. Cute!