I am not sure what to do for the day in Grand Cayman. My daughters are 8, 10, 12 years old. In Cozumel, we are doing Pleasure Island. Grand Cayman not sure. Jamaica just Margarittaville pool and Castaway we are enjoying the beach. I don't want to spend a fortune on excursions. I am fine just getting off the ship and walking around. Am I missing out if I don't do something special in Grand Cayman? Is the turtle farm that amazing? Any other suggestions?