[Vautrin]

Parenting skills are of course vital. Without parenting skills, a divorce does not make too much of a difference.

Without parenting skills, you either spoil the child beyond belief, or you don't give a thing about what your child experiences and goes through (basically the same outcome, but with less of an entitlement belief).

But of course a parent cannot control everything. There are influences from outside the family. We can think economic influences (a parent losing their job), but also the influence of peers. Random influences (traffic accidents), et cetera.

Ivan Illich wrote: "The public school has become the established church of secular society."
A lot of people don't teach children morals, don't give their children direction in life. Partly that is due to economic pressures, as more and more both parents work outside of the house, for longer and longer times. This has to do with declining real wages, and of course hits the lower and middle classes harder than the upper classes.
But it is also partly due to the fact that they don't know themselves where they stand in life, and what they can attain. This is somewhat related to the 'instant gratification' society promotes. If you can only think of the immediate, how can you think of the long term consequences of your behavior, and how it will affect those around you?
School replaces the family unit in teaching morals. Which they don't do, but everybody seems to assume they do.