policy4ev said:
Does the parent not have to change the way they punish kids to make sure the kids get it. It's not only the parents that are different. If one punishment does not work on a kid, then the parents have the responsability to try something else. If they don't they might as well give up on the kid!
I'm not sure what your point was, but if it was supposed to address mine it doesn't.
I contend that most parents either use physical punishment with all their children or with none (possibly with some difference between how boys and girls are treated). That points to its use being an inadquacy in the parents, not a function of the children.
Similarly, I suggest it is more common for one parent to use physical punshiment on both children while the other does not, than for both parents to use it but only on one of their children. Again, that points to its use being a function of parent not of child.