In ORD the DEL flight tends to leave from the high K gates (like K19).
It is a good hike from the H/K crossover at H/K 6.
There was another post recently about ORD kid-friendly areas and I seem to recall there is a Kids Playland of airport authority making at the H/K to L main hallway (inside security). Tho that puts you even farther away from the departure gate (I know I know walking will wear him out right??).
While I hope your son can charm the AC AAngels .. there really is no good play area within the ORD Club (and you are Business and PLT so the Flagship is out right??). The one thing you MIGHT consider if you have a long layover in ORD is to rent a room in the Executive Conference Center (floor #2 while the AC is floor#3). From the information online
http://www.aa.com/content/travelInfo...sChicago.jhtml there are 26 meeting rooms .. tho drinkies would have to come from the AC upstairs... Not sure how much time you have in ORD vs the cost of rental .. it may be an option.