So it's ok to take your eyes off a child if they are obedient? So maybe this obedient kid was sitting on the floor with a car going, "zoom zoom" and the mirror fell over on him.
But you have said REPEATEDLY that the mother should NEVER have taken her eyes off the child. NEVER.
You will get no where with that line of reasoning. Her mother, and she and her siblings were perfect.......this woman was negligent.