We traveled in the mommy van with our 4 kids and a potty-training pup when we moved from GA to MO this past summer. It was quite the adventure! I learned that traveling at night ensures that children sleep most of the way. (By the way, we traveled during the day. Bad idea.) It's important to make the most of rest stops by allowing kids to stretch and run around for a bit. Having lots of snacks and activities on hand are also crucial.
Traveling with 4 children from KY to HI is another story. Just give them Nyquil.