And they're right — their children really are good people, living the gospel and treating others kindly and raising their families and doing their jobs to the best of their ability. But who is blessing whom?
We can certainly be grateful to our Father in Heaven for having chosen to send us children who are disposed to do good.
But it's a core doctrine of the church that God did not make them good. If we have good children it is because they have chosen to love the Lord with all their heart, and then to love their fellow children of God.