Does a divorce that was made contingent on something bad happening to the child take effect, and how many divorces take effect if something bad does happen, knowing that divorce has previously been entertained in the mind many times, uttered many times, and not uttered many times?

Thinking about divorce to oneself does not constitute divorce. However, if you utter a conditional divorce, contingent upon a disliked event befalling your child, then the divorce occurs once that disliked event takes place, counting as one pronouncement. You may reconcile with her during her waiting period, provided you have not divorced her more than once.