Mine always go in the cage. The longest journey I have had for a puppy was Miar who came from Scotland. She was brought to Birmingham for us, and we picked her up outside the show. She did yap a bit at the start of the journey (in Scotland), but that was probably just cos she was leaving Mom. We never had any problems with her.
When I breed, I always try to take the pups out in the car a couple of times before they leave us, then they are used to the motion.
Only ever had sickenss problems with my first Welsh, but then she lived with my mother for her first few months and my mom's driving can be interesting

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I did once hear someone say that their line had sickness problems, so maybe there is a genetic component?
Basic answer for your friend is do what Sue suggests and RELAX