12:45 - 9 and then the surrounding parts are open earlier and later. We got there around 2 pm and stayed thru the end of the Breath of Life show which ends at 9.

By getting there are 2 pm we didnt get to see all the different shows at each land, so we missed a bit there. My wife and I would have liked to have seen all those, our 3 kids had more than enough. If you're taking your son and DIL they'll probably be a lot more interested so I'd say do the full day.