>>Just thinking out loud... why can't adults wait until the child in in their teens before cruising?
I'll field this one. I do it primarily so my kids will have fond memories of their childhoods. At 50, I remember a lot of my childhood, but I especially remember the travels we did, and some of the thrilling activities I did.
My daughters (ages 16 and 11 now) have (so far) swum with stingrays (Grand Cayman), swum with dolphins (Cozumel), inner-tubed thru a cave (Belize), and zip-lined thru the rainforest (also Belize). On our next cruise, we'll be kayaking in a bioluminescent lagoon (San Juan) and parasailing (Half Moon Key). These are memories they'll have forever.