Thanks for your advice so far.
Kenosha to Louisville is only 6 hours if the kids sleep. My husband is a real night owl, so I thought driving, say 6:30 to 12:30 was reasonable. (We will split drive time for the duration of the trip.) But that would mean driving through Chicago 7:30 Friday night. I have no idea if thats a bad traffic time. And it would mean our first night on the road may not be a long sleep.

I too was concerned about driving to the coast after a day at Disney. We have been to Disney before the kids, and my husband keeps assuring me it's no biggie. I'm not as sure.

Sounds like this plan needs some tweaking. I was trying to avoid days much longer than 9-10 hours in the car, but still allow enough time to spend on the gulf coast.

I'd love to fly and drive! I'll check into it. I'm actually looking at June after the kids get out of school.
We have a drive to Minneaplois coming up, so that will give me a better idea of how the kids tolerate long driving.