Prince William and Kate Middleton, often considered the epitome of royals, have broken rules in the past. They cannot give autographs, engage in public displays of affection, and must get permission to marry.
They also have to follow the rule that heirs to the throne cannot fly together to protect the royal line. This rule was established to ensure stability in case of a plane crash.
In 2014, the couple broke this rule with Queen Elizabeth II’s permission, traveling to New Zealand and Australia with their son George. William adhered to the travel code until he was 12.