Family is the first culture to which children are exposed. What happens there affects everything else. But a fine family can't force physical development on anyone. It can't restore vision or make someone grow faster. What it can do is offer an assortment of alternatives, and to show what is of intrinsic value by demonstration.

The family of a reader reads. Yet sometimes, reading families produce a non-reading child. It's up to the family to seek remedies and alternatives, including understanding the child's developmental pattern. If the family can do that, the child can learn through other means than the average how to master the valued skill. If the family can't or won't do that, the next level, the larger society, usually in the person of the school, is the child's next opportunity.

Non-reading families will produce readers too. Sometimes it's by accident. Sometimes it's through effort. The "accidental" readers will often have siblings who are not so fortunate.