3. There Must Always Be A Mourning Outfit Nearby
When traveling abroad, every royal member must pack an all-black outfit in their suitcase in case of an unexpected death.This became a rule when King George VI died, and Queen Elizabeth rushed back to England on a plane from Kenya. She couldn't disembark until she had a mourning outfit on, and had to wait in the plane for hours until it could be fetched. In order to never encounter that problem again, the rule was established.