When the Duke and Duchess of Cambridge welcomed their second child, a beautiful baby girl, six years ago today they named her Charlotte Elizabeth Diana.
It was announced that she would be formally known as Her Royal Highness Princess Charlotte of Cambridge thanks to her position as fourth in line to the throne.
While she'll use her HRH title throughout her life, it's not exactly very practical for a six-year-old at school so Kate and William have styled it differently.
In the same way that Princes William and Harry took their dad's title, Wales as their surname when they growing up, George, Charlotte and Louis use Cambridge.
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