I don't have any suggestions about car sickness - Zeus is fine so I don't have any experience.
But regarding everything else, make sure to bring a container for water. ESPECIALLY if he gets sick. He'll need those fluids. You can get those collapsable bowls or a plastic flip kind (kind of a like a water bottle at the top that folds into the actual bowl).
And then of course the obvious...food, any treats that he likes and his favorite toys. Zeus is really attached to me and loves his car seat but on long trips I've found it helpful for him to have a sweatshirt or something of mine. We will be taking a longer trip in April and when we do, I'm going to have one of his blankets in our bed and use that instead of a sweatshirt. It helps him calm down (he'll whine to come sit on my lap. And I'm the one driving...haha).
If you any type of chews (whether food or a toy), bring that for the long ride. It'll help as a distraction.
__________________  Heather Zeus  | Thalia  |