Kate Middleton is often praised for her staunch approach to royal protocol. The future queen consort rarely missteps when it comes to the rules and regulations of royal life. That's why a small slip-up at recent engagement is making headlines.
While attending the G7 Leaders Summit in Cornwall, England alongside Prince William, Prince Charles, Queen Elizabeth, and Camilla, Duchess of Cornwall, Kate made a slight error when greeting her father-in-law. According to Cornwall Live, Kate cheerfully greeted Prince Charles when she arrived at the event, saying, “Hello, Grandpa! How are you?”
While this is likely how Kate greets her children's grandfather in private, she is supposed to follow official royal protocol when she's in public. This means she's supposed to refer to "Grandpa" by his official titles—His Royal Highness, Prince Charles, or the Prince of Wales.
With so many names and titles to keep track of, it's hard to blame Kate for breaking protocol. And, surely, "Grandpa" is one of Prince Charles's most important titles at the end of the day.