E.W.
Imagine twins that got car sick! My understanding was that watching things whizzing by out of the window IS what makes them car sick. We tried everything from screens to block out the scenery to home made little blinders for the car seats. What worked was toys that hung over the front seat that kept them busy front ward, books and later a DVD player. Just about anything that kept them from looking out of the side windows.We tried not to leave immediately after meals and keeping meals light. We also carried lots of cleaning supplies and extra clothes. Good luck. E.