This summer we drove from CO to MI stopping in KS..... with kids ages: 3,5,10&13.
We decided to drive during the day. We left around 3 am the first day, got to our stop about 9 hours later, stayed over night, well, left again at 3 am and got to MI somewhere's around 7 pm.
The kids did great in the car, they were a bit crazy at times that is when we would have them run around a bit when we stopped!
But we figured that it was safer for us to drive in the day. Not only for our sleep, but other sleepy drivers on the road, or drinkers....
Best wishes in whatever you decide!
Have a good trip!