Another day, another weird royal family fact! According to the British newspaper the Express, Kate Middleton isn't allowed to sign autographs while greeting fans at public events. So weird, right?!

MORE: The Royal Family Is Banned From Eating Certain Foods in Public — Find out Why!

Apparently, the Duchess of Cambridge isn't the only royal family member who must refuse autograph requests. Kate's hubby, Prince William, her brother-in-law Prince Harry, father-in-law Prince Charles, and even monarch Queen Elizabeth have been strictly instructed to not display their signatures. What is the reason why, you ask? Watch the video below for the fascinating answer!

Interestingly, Kate's autograph ban is just one of the many rules the mom-of-two has had to follow since marrying into the royal family back in 2011. She must also never be seen crossing her legs at the knees (at the ankles is ok, though!), should never show cleavage, follow strict tiara-wearing protocol, and demonstrate a perfect curtsy, according to AOL.com. Being a princess doesn't sound totally easy now does it?

kate middleton autograph getty images

Earlier this week, another report about the royal family's strange rules surfaced that stated William should never travel on the same airplane as his wife and kids — but he does it anyway! The Sun revealed it is unofficial protocol that heirs to the throne (aka the Queen, Charles, William, and Prince George) are not supposed to fly together in case of a dire accident. But since air travel has become much safer over the years, Queen Elizabeth has become more relaxed about that guideline. The more you know!

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