On a cruise, I would not let my child whether boy or girl go without me unless they were maybe 16. First, communication is very expensive and you might not even get service on a cruise. If you want to check on them it would be very, very hard and very very expensive. Second, mexico is very unsafe with the drug lords. I won't even go to mexico. If the trip was in the continental USA I would say yes. Then you can always check on them. Remember that poor girl who disappeared in Cancun. My son is 19 but I was never over protective of him. However I would not have let him go on a trip like this. I watch too many shows on investigave discovery where young kids go missing. Just recently I saw an episode where a young girl asked to go to North Carolina (I believe) for spring spreak. Mother said no but the daughter lied and went anyway (said she was staying with a friend). Anyway, one day while she was walking from one hotel to another, she just up and disappeared. They have surveillance of her right before she disapeared. So I am very skeptic about letting someone actually watch my child, especially on a cruise where I am sure the adults are going to be on "vacation" also. Think long and hard before you decide. Maybe your family can take a cruise together.