Kate Middleton just broke royal protocol during her latest reunion with Prince Charles.
The Duchess of Cambridge, 39, recently attended the G7 Leaders Summit in Cornwall, where she addressed her father-in-law by a personal nickname: Grandpa.
According to a lipreader (via Cornwall Live), Middleton immediately greeted Prince Charles when she arrived at the event, saying, “Hello, Grandpa! How are you?”
If you’re thinking, why is the nickname such a big deal? You should know that it’s protocol for members of the royal family to address each other by their official titles, especially in public. In this case, Prince Charles, His Royal Highness or—dare we say—Charles would have been more appropriate.