This woman is guilty but it is a sad case. Her husband is not guilty of killing the children but he is guilty of choosing to see what he wanted to see and have more children with a mentally defective wife even though she could not handle the ones she had. Did he care that the mental disease could be passed on to more children?
When Andrea called him at work - she said "I've finally done it" (or something similar). So, she must have told him earlier of her desire to kill the children. If she had not, she would have said "I've done something to the children". If she had told him earlier - why in the xxxx didn't he arrange for those children to have someone else there also. Why didn't he then get them into public school where they would be away from a mother considering killing them?
IMO he didn't because he refuses to see anything but what he wants to see. His desire for a traditional family with his wife teaching them is more important than the fact that his children are in danger. With a sick and dangerous mother, the children need to look to a sane father to see that they are protected - he failed them.
He may not be guilty of murder but he failed those children and now they are dead. What about his traditional family now? Another thing, how can a man continue to love and protect a woman who has killed five of his children. Where is the anger, and fury?