I've been asked to use AC in ORD when we tried to use the FL. It was myself, EXP, and my wife and 1 year old both PLT. The 1 year old was throwing a fit, when we walked in to the FL. I was a little bit peeved but they did have a point, the AC has a kids room were as the FL is pretty small.
That's the only time i've been denied when entering a OW lounge with my whole family. Now the 1 year old is 4, an only had gold, and we've got another 1 year old, who doesn't even have gold yet. We've used AC's all 4 of us without a problem.
The AC's do think it's very funny that a 1 year old can get in to the AC on is own status.