What is the worst thing parents can do to their children?

The worst thing the parents can do to the children is either burnt their skin with boiling water.it really sounds very cruel, isn't it?the parent can also beat them like very rough when they fell very angry or when they are in a foul mood.all this thing that happen saddens me because those parents who did that is really cruel and i also wished that no parents would do this to the children. i feel very blessed because my parents are good to me.