Minors are not permitted to disembark the vessel without being accompanied by an adult. Princess passengers receive a medallion that can be worn on a lanyard, wristband, etc. The medallion has your photo along with other identifying information. The medallion serves as your room key, onboard purchases, food/beverage ordering, etc. The medallion lets crew members and other ship personnel know your whereabouts onboard the ship. I'm curious about how Aydin managed to disembark without his grandmother because his medallion would have alerted security personnel that he was a minor and had to be accompanied by an adult to leave the vessel. My guess is that Aydin was in line to disembark as soon as the ship was cleared by local customs agents. There were likely hundreds of passengers eagerly waiting to get off the ship for shore excursions, exploring on their own, shopping, etc., and it's possible that security personnel couldn't keep up with the crowd.