I had one that was really awful in the car, throwing up and even pooping sometimes. Once i took her on a really long car trip she got over it.
Oh wow that sounds miserable! Glad she eventually got over it though.
I am not sure exactly how bad Frank is but I figured with more exposure he should eventually get over it? And/or hopefully just grow out of it because he is still a pup. They are gone for the weekend so I am sure they will probably be making lots of short trips and hopefully on the way home he will be better.