It's great that you want to keep an eye out for the little boy with the red flags...some parent's welcome advice and some don't, but it definitely never hurts to try! I always think that either someday they are going to appriciate that someone cared enough to help, or they will say that woman was crazy because our child is fine...I always hope it's the latter, but in either case I have peace with myself at least. I'm one of those people that wished people would have done that with Mason when he was younger. I was very uneducated and had no idea what I was dealing with...and honestly I think I get more out of what people have told me than I do out of the doctors.
Take care!