Hi:
We have driven down 5 times from Hamilton. We usually leave at 4 or 5 a.m. and stop just after supper. I always book two motels about 1 and a half hours apart, that have the either 4 or 6p.m. cancellatiion rule, so that when we are close and know which one we will go to I call again(from a welcome center or wendys etc) and give my credit card to hold for a later arrival. Always we choose a motel tha offers a continental breakfast for a quick bite to eat and back on the hwy. We like country inn and suites, hampton inns, fairfield.
For Canadians grabbing a bite for lunch etc, Wendys 99C meals are great for the budget. They have salads, fries, hamburgs, chilli, baked potatoe. We found this out on our april trip.
For washroom stops make sure you go to the rest centers that have people working in them, such as the welcome stations for each state, or pull off the hwy for a fast food restaurant.
The one reason we don't drive thru the night in winter are the mountains, you don't know how the roads will be there, whether snow, fog, or icy roads. Especially with children in the car.
Take lots of snacks, and medications for whatever and throwup bags, pillow, blanket for your child. You just never know. Sorry for going on and on. Don't try to drive straight through on the way down, you will be whipped for your wdw vacation.
We drove straight through coming home only once from daytona, (19 hrs from I95/79/77 thru virginia, dont do this route in the winter) but my hubby still had a couple of days off and we knew we had a bed waiting for us at any arrival time. Have a great trip.
Debbie.