Not true Legend. You will need a written notorized letter from any absent parent to take a minor child on a cruise. It is Federal Law that makes it illegal to remove a minor for the jurisdiction of the USA without the consent of the absent parent. If they ask for it and you cannot produce it, you will not be allowed to take the child onboard. Is it always done or asked for? No, but if it happens then your vacation is ruined and that isn;t worth it.