I stayed at the Marriott last October. Onsite dive shop (Caribbean Sea Sports). Morning 2-tank trips, mostly north of resort, good reefs, unlike dive sites south of the town which show signs of overdiving. Free tanks for shore diving included in daily dive price. Nice beach, with relativelty shallow lagoon created by rock barrier. I'd check directly with the hotel about kids' activities. You might end up alternating diving with your spouse. There were never more than 5 or 6 other divers (one morning, I was the only one, and the boat still went out), but if they have enough, they do an afternoon boat dive.