I'm sorry, case law is outside the scope of the original question and, since it requires substantially more work and some expense to access the legal databases, has to be done through the Additional Services button.
However, you're not going to find anything that is much help. The concepts of the law are what I have discussed and so all you will find in a case law search is cases where they discuss specific facts, usually involving the child spending time either in a day care or with someone other than the parent as opposed to the child spending time with the other parent.
Things like the torn pants will help, be sure and save those, make notes, and take pictures.
The best way for a father to win these kinds of cases, and the reason I won most of mine involving the father, is that I was hired well before we filed to change the order and we began "setting things up". These situations are really like a chess game and you want to have all of your moves planned out and set up before you make them. Whichever lawyer you hire will do the in depth interview, find the weak points of the mother, and then begin to exploit them before the mother knows the lawyer is involved. In addition, the lawyer may want the child to see a psychologist or psychiatrist and, if you are in a small enough town, get an ad litem appointed who the lawyer knows will be favorable. This can also be done if things are set up early and followed through to the end of the case.
If you choose to add the Additional Service, someone else will actually do that, I only handle the exchange of information through this type of forum.