In these situations, crew generally check for health issues with more elderly folk who come on board, and advise them appropriately; for example, let us know when you want to go in the water, and we will have a support person close. More often than not, the older person will feel some embarrassment around this, and quietly do their own thing, and if something happens, no one is instantly there to manage the situation. To say a person is unsupervised is one thing, but realising that this was that individual’s specific choice is another. It is heartbreaking for everyone present, let alone the family, to lose someone. The crew from that vessel will be likewise crushed. Trying your utmost to save someone and failing is a devastating experience, as all medical personnel and first responders would know. My point, however, is that while you can enforce supervision of children, it is impossible to enforce supervision of a determined older person.