Sometimes you just have to kick someones ass or at least make the attempt. It's as plain and simple as that.

However, as the above poster proves, not everyone is capable of doing so.

I suspect parents may have been lacking in the self-confidence giving part of their child rearing responsibilities in cases such as this. I am not casting blame, especially since this is all supposition, however, I have worked with kids for many many years, in my roundabout way, I have seen with my own eyes how this works.