Well unlike other responders I think it depends. I did not put my 3 year old in a pull up on the way home from the shore this summer(it was mid afternoon), he has been PT for well over a year now with no accidents in as long. I didn't even think about it. He fell asleep and peed in the carseat which leaked through onto the cars actual seat and I can tell you it stank and I wish I had used a pull up. It was crazy hard to clean and get the stink out. My 6 year old still sleeps with a pull up on, and though I would not consider putting her in a pull up for a trip she was awake for(even a long one), if I thought she might fall asleep, I would put her in one. And from now on my son will be in a pull up for a long trip where he too might fall asleep. So I would say if he never needs a pullup at night then it won't likely matter if he falls asleep, you can skip the pullups. But if he still has accidents at night or uses them at night I would put one on him, especially during times he might sleep. And this may horrify some of the other responders here, but in March when my daughter was still 5, we were in Disney World, and on a train ride that took over 30 mins and of course it was a ride so couldn't stop or get off to pee, and I put one of my son's pullups on her when she had to go, and she peed in it after some coaxing, and she felt so much better and was able to relax and enjoy the ride. Sometimes we just do what we need to do.