The royal family is keen on giving each other nicknames. Siblings Prince George and Princess Charlotte call their younger brother Prince Louis "Lou Lou."

At school, George's friends call him "PG" or "Tips," which is "based on the popular tea brand PG Tips and his initials, Prince George," the outlet said." The name was so well received that William and Kate adopted his nickname at home as well." (We have to say, it's a pretty clever nickname for young children to come up with.)

Charlotte's friends at Thomas Battersea School in London, where George also attends, have taken to calling Charlotte "Lottie."

Kate is a nickname for Catherine, the Duchess of Cambridge's birth name. And Prince William has a childhood nickname given to him by his mother, Princess Diana." Wombat."

"It started when I was two years old," William said in a 2007 interview with NBC. 'I don't remember it being that long ago, so they took me for granted. But when I went to Australia with my parents, wombats are a local animal. So that's basically what they called me. Not because I look like a wombat.