Okay, nice and fluffy me on the thread now.
The point of the OP is people being judgemental of situations where they don't have the full background (i.e. DS has SN). People are programmed to judge situations (for danger etc.) and they can only judge on the information presented to them.
This is something that is taught on Diversity Awareness courses and the following situation was given to us:
A number of people are stuck in the bottom of a well. The well is collapsing and there is no guarantee that everyone will be able to get out so who should go up the escape rope first? A few of the examples were:
Teenage boy who has been drinking.
Elderly man with a serious heart condition who needs regular medication or he will die.
24 year old Nurse.
All of us said to get the teenager who has been drinking out because drunk people can be violent/hysterical etc if they panic which would make things worse. The Nurse should remain to help anyone who has been injured by collapsing rubble. The elderly man should go out first because of his life-and-death need for his medication.
Then we were given more info about the people.
The teenage boy had indeed been drinking - orange juice. He has a first aid certificate.
The Nurse has a knife and is threatening to kill everyone unless she is allowed out first.
The elderly man is a GP who has a weeks worth of his meds with him.
Of course our opinion changed once presented with the full facts however the course leader said it was perfectly natural to make judgements based on the limited information available to us.
Unless the OP is going to get her DS's medical history tattooed on his forehead then she should keep her temper in check and politely 'educate' people about her son.