To refer to royal families, you use "Royal Highness."<br/><br/>But I'm not sure the use of 'possessive' in front of it :<br/><br/><b><u>Your</u></b> Royal Highnesses, Lords and Ladies of the Court and our distinguished guest from the forests of the New World.<br/><br/><b><u>Their</u></b> Royal Highnesses, the Duke and Duchess of Kent.<br/><br/>Can you tell me the difference between "Your" "Their"?