On our cruise to Alaska last year, there was a group on an incentive trip, and some of them were families, probably two dozen kids total - mostly older than 5. They were not a problem, running rampant or misbehaving at dinner. I have no idea what the children's program was like, but expect it met Radisson standards. You know your kid - will she/he be confined on a boat or enchanted? I wouldn't go on a Carnival cruise just to please him/her. We took a 5 year old and an 8 year old on a 3-week trip to Europe by train many years ago [they're now 32 and 35] and we all still remember it fondly.

David