How can I help out my brother-in-law who is a private in the Army who just found out he is a father?

My brother-in-law is a 20 year old with a mind set of a 14 year old boy. He just graduated from basic and training two weeks ago. He took a paternity test and found out that he is the father to a two month old boy. He has orders to take him to Korea in the beginning or middle of July. He is on leave at the moment but he is running out of time fast. He is in the Army but where he is on leave there is a Navy base around 30 min away. The mother is an absolute train wreck. She doesn't bathe the baby but every three or four days and the baby has horrible diaper rash. The poor baby has open blisters and she doesn't know how to properly change a diaper to keep the baby dry. Well my b-in-law cannot get the mother onto base now because she has no picture ID, no driver's license, or state ID card. She cannot get on base to set up child support or set the baby up as his dependent in the system. (I know alot of this stuff because I am a veteran and I am an air force wife.) He is running out of time fast and I have no idea what advice to give him. I wish there was a way to extend his orders. He found out just last week that this is his child and it is completely the wrong time. Not to mention that he is immature and is not taking the right steps to maximize the time that he has left before he has to report to his duty station! Can anyone give me some advice on what to tell him?!?