Kate revealed her school nickname to pupils of her former school.
The Duchess of Cambridge Kate Middleton revealed her childhood nickname while visiting her old school, St Andrews, in Pangbourne, Berkshire.
She told pupils of her former school that she used to be called "Squeak."
It was inspired by the school's guinea pigs, according to OK magazine.
"There was one called Pip and one called Squeak, so my sister was called Pip and I was Squeak," she said when she spoke to pupils.
The duchess, who was born Catherine Elizabeth Middleton, was apparently always known as Catherine by friends and family when she was growing up, according to CafeMom. It was only when she went to university that she began to be known as "Kate."
Middleton is not the only royal to have an amusing pet name. The Duke of Edinburgh is understood to still refer to The Queen as “cabbage”.
The nickname emerged after the 2006 film The Queen was released. Phillip says to Her Majesty — who was played by Dame Helen Mirren — "Move over, Cabbage."