Kate and William have an unusual but adorable nickname for Prince George

Prince William and Kate Middleton have a super cute but unusual nickname for their eldest son, Prince George, that they gave him when he was just a baby.

Prince George is the oldest of the three Wales children and the one who made the Prince and Princess of Wales parents for the first time when he was born in 2013.

Young George, who is second in the royal line of succession after his father, no doubt has a very different life to other boys his age - but Kate and William are known to be keen on making his childhood as normal as they possibly can.

And just like most 10-year-olds, George has a rather sweet nickname that's used at home at Adelaide Cottage, where he lives with Princess Charlotte, Prince Louis and his parents.

According to the Mirror, Kate and William gave their son his nickname when he was just a few months old, with the sweet moniker stemming from both his initials and a quintessential British staple.

Back in 2013, the publication reported, "Proud royal parents William and Kate have given their new son George an unusual nickname – after a brand of teabags.

"Pals started calling Prince George PG, so the couple took the next logical step and dubbed him Tips."

Princess Charlotte and Prince Louis have their own special nicknames given to them by their parents, too.

While Kate is known to call Prince Louis "Lou-bug", Prince William has previously been heard calling his only daughter "mignonette", a pretty word that means "delicate" in French. Although the nickname given to Charlotte at school has rather contrasting connotations.

According to royal expert, Katie Nicholl, Charlotte earned the name of "Warrior Princess" at her first school, Thomas' Battersea.

"Apparently she earned that nickname because obviously, she is a Princess, but she's quite a tomboy," Katie told Entertainment Tonight .

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"She loves climbing trees and she's very much an adventurer, she was quite known for her feisty personality. I'm wondering if that might be a nickname that will stick with her," Katie continued.