@talisman, I understand what you are saying here, but still be very cautious. If you were to say any of this to my friend she would be deeply hurt. You do not know what else the parents are dealing with and in her case leaving a physically abusive spouse and having cancer twice are things that may have affected her son, and she does not have any interest in learning more at this point. She was beaten, she left as soon as she could, she was not given any financial assistance in 14 years, and no protection because her ex is a cop. We can say all of that was wrong and they are long since over, but I will tell you that if you suggest anything like what you said to her or another parent you will in fact hurt them deeply.
A few weeks ago when she was too sick to stop throwing up for a week and no one in her family came to help she felt guilty about his behavior. She feels guilt for being abused, guilt over getting immunizations, guilt for buying the wrong type of milk. It seems to me the best move is to express deep compassion for the parent who is willing to keep working at it instead of putting the child in an institution so that the autistic person will have the love of family and reach their best potential, whatever that may be is not ours to judge.
Oh yeah, I forgot my other part. If this seems to be more than just a one time incidence, like boss 2 brings up the crying again and again, then I would have one of those difficult conversations with him about it. Being 2 months on the job and just learning how people handle problems is different than being the office crier.