I once witnessed a child being treated cruelly by a parent in the street, and also a child behaving very badly in a train. On both occasions, with thumping heart, I expressed my disapproval of their behaviour. In both instances, I was greeted with venom and invective, not to mention threats of violence by the parents. However anti-social people are, they resent being criticised by a third party. Instead of becoming self-analytical, they just spit out insults, claiming that it is none of your business.