Jesika, I wish you the best. But I hope you know to be prepared for anything. Outcomes are not always what we expect, and even judges can misjudge character.
The important thing for you to remember is to describe behaviors which hurt your son. Leave feelings and speculation out of it. If you haven't done so already, make a list of destructive behaviors exhibited by this person in the past, with time frames as accurate as possible. Your attorney will need any and all FACTS you have at your disposal, preferably in writing. It's a lot of work, but it's worth it.
Keep us posted.
SandraC