I remember being your age and having little to no say on pet related issues, so, you probably couldn't convince your dad to keep Max even if you showed him this thread and talked to him (I'd still show him the thread, though, it can't hurt). I know we had to rehome a cat when I was young, and, I had nothing to do in that decision making process. (although, being an adult now, and, hind sight being what it is, it was the best decision in our situation at the time) I will say that I agree with Vela in telling your parents that if they're going to get rid of Max, that they shouldn't get another dog. They may take that thought into consideration as it shows maturity on your part. Good luck, no matter what happens.