We have cruised dozen or more times - just rt'd from the same cruise on the Nordic Empress. Don't book the ship's tours . You can do things yourselves easier and cheaper than the ship and safely, too. Try to meet up w/some friends -new or old - its fun to do these w/a group.
Grand Cayman - snorkle right from the shore right near the tender docks at Eden Rock/Devil's Grotto. Bring your own snorkle stuff or rent there. EASY walk from the tender, great snorkling, no need to use a boat. In fact, we snorkled right past the snorkle boats that were anchored at Eden Rock! My sons are 19, 21 and took a semiprivate scuba lesson and 40 foot dive there for $70/person and had a terriffic experiece. My husband and I snorkled the same area - LOTS of beautiful fish. Or, Stingray City but rent from one of the tour operators on the shore - cheaper and easy.
Belize - Cave tubing with Reggie. Hands down winner. Go to www.regtours.com
. $65/person and you'll have a great time. Nothing like you've ever done and perfectly safe for you daughter. Easy walk through the jungle, then float on an inner tube through caves and the jungle. Gentle ride and a blast. You may want to bring a life jacket if she is small, but if she is comfortable in the water, there is no need. Longer ride than with the ship and $30/person less money! Just get up early to get early tender tickets to get off the ship early in the day.
Cozumel- Cab ($10) to Chakanaab ($10/person entrance fee) to relax, beach, snorkle, swim w/dolphins (extra charge). Or, rent jeep from Budget at the pier ($65/day) and spend the day the way you like. SanFransciso Beach is beautiful and free, you can visit some Mayan ruins (marginally good), and go to Chakanaab or Palancaar reef. Other side of the island has huge waves for body surfing and just admiring.
Write me if you want more info. We had a great time at these ports.