Don't forget that there will be several FREE cooking demonstrations held each day around the world showcase - and your Son would certainly be welcome (I wouldn't try to bring my 4 yo son, because he would be bored and would act up which would be disruptive and disrespectful to the other guests - but your son sounds like he would truly enjoy them)....You can find out the times and locations from the food and Wine Fest booklet that will be avail at the front of the parks once the festival starts.
For instance - last year, they had a chocolate cooking demo in Italy - the Italian Chef made pasta with Chocolate with a red pepper sauce - we all got samples - it was yummy, and free! The "celebrity chefs" will also do cooking demos.....