Train a child in the way he should go, and when he is old he will not turn from it. The others believe that if the child ever rebels, even when he is grown, then the parents obviously did not raise their child right. The Scriptures speak of children in many ways. Parents are told to do certain things with them, and children are commanded to also obey. Pastors are especially commanded to maintain domestic order in Paul's letters to Timothy and Titus.
Children depart from their parents' ways.
The Ammonites and the Moabites both became enemies of their cousin Israel's descendants. The story of Joseph and his brothers shows how jealousies and wickedness can grow - even though the parents may have not neglected or mistaught their children in any way. Eli knew better, yet didn't follow through. He and his sons paid with their lives. The same David who composed this Psalm had a son who rejected his father's teaching and tried to kill his father, but the Lord seemingly didn't hold David accountable for Absalom.