Do you have any "safe" foods you could bring in the car? For me, it's unsweetened applesauce, bananas, saltine crackers, hardboiled egg whites, and Rice Krispie bars. Baby food could even be an alternative. You could even cook a plain skinless boneless chicken breast, shred it, and keep it in the cooler to put on crackers or plain bread. I know not eating works for some people, but for me it's a sure trigger. Not only will it set of my acid reflux, but eating anything on a very empty stomach guarantees D for me! And most importantly, have fun!! I travel a lot... I live 1500 miles from my family and my hubby doesn't like to fly, so we make the trip at least twice a year. So I know how you feel. It's always a concern.