The most important thing is to admit what comforts your kid. Does your fifteen year old still sleep with his blank y. Then you better pack his blank y. Haiti is so alien that I have seen seasoned travelers have complete meltdowns. Before you commit to going own the fact that there is a mortality rate associated with in going to a third world country.
1) What makes them comfortable.
3) Bug repellant
4) Water bottle
Take the medicines your doctor gives you. I choose the Haitian Tap-Tap to travel in I think this provides a more engages trip. The smells, sounds, involvement with Haitians is added. But nice AC vehicles can be found for the same price.