Haven't read all 7 pages of replies, sorry. For your carsick youngster, here are a few suggestions from a champion cookie-tosser.
First, have him sit toward the back of the group, so he's always facing forward. Turning one's head to talk, especially facing the rear of the vehicle, can make some people sick in a blink. Second, stay seated while the coach is moving. If he's moving one speed/direction and the RV is moving another, he might get ill quickly. If he must get up to use bathroom or whatever, make sure he is always facing the windshield. Third, games, reading, even watching movies may not go well in an RV that bumps and sways. Last, ask at the pharmacy counter for children's Dramamine, just in case. I also find that an instant cold pack (for sprains) applied to the throat calms nausea. The front passenger seat is best, if you can make that work.
