I'm going to assume your son was either 11 or 12 years old, which means he was in the "overlap" age and could attend either the Club/Lab or Edge. He would need the band for the Club/Lab, but not for Edge. He could have taken it off for Edge, though then there's a risk of losing it and being charged. Those age 13 or 14 would not receive the bands at all because they are too old for the Club/Lab.
Enjoy your cruise!