The basic problem with this theology is there isn’t any convenient place where you begin to hold anybody morally accountable...and as any parent of a toddler in a tantrum knows...good luck with that!
A child’s tantrum isn’t a function of conscious sin, but environment. Change the environment and a child needn’t throw a tantrum. Ours never did. We noted that every tantrum came from one or a combination of four things: tiredness, hunger, sickness or frustration. It’s an opportunity to learn for both child and parent not evidence of a sinful nature.