When you think about friends, family or anyone who you love, you can often find yourself forming affectionate nicknames - some of them stick and some of them don't, and often, they're nothing like the person's real name.
Just like in every family, members of the royal family also have endearing names for one another, from Prince Harry calling the Duchess of Cambridge 'Cath' instead of 'Kate', to the late Prince Philip being referred to as PP.
Similarly, the Duke of Cambridge has an adorable little nickname which he has given to his daughter, six-year-old Princess Charlotte - which just so happens to be a different nickname than the one used by Kate.
