Royal titles can be difficult to follow, particularly as they change with marriage, succession, and shifts within the monarchy. Catherine, Princess of Wales, for example, was widely known to the public as Kate Middleton before becoming the Duchess of Cambridge and later assuming her current title—though many people continue to refer to her simply as “Kate.”

Before Prince William’s wife officially joined the royal family, there was one very strange suggestion floating around. Who could have imagined that the spelling of Kate’s name would be such a significant issue for Charles and Camilla? She wasn’t asked to change it completely, nor was she told to pick a new royal title. Kate was kindly asked to swap the “C” in Catherine for a “K.”

That’s right, the most nontroversial drama in recent royal history revolved around just one letter. According to Prince Harry’s memoir Spare, the issue stemmed from the royal ciphers used for personal monograms that royals use on stationery, gifts, uniforms, and official items. Charles and Camilla already had ciphers involving the letter “C” under a crown, so adding another royal “C” was apparently too confusing, so they suggested Catherine become “Katherine” instead.

Catherine Elizabeth Middleton was born with that spelling, and by the time she was ready to marry Prince William, she had already spent years dodging paparazzi and being featured in the news. “Kate Middleton” was the tabloid-friendly version everyone knew, but “Catherine” was her given name, and the more formal version suited to royal life. So reportedly, the idea of changing even one letter just to keep palace branding neat felt pretty insulting.