Agree with Marie.
If this grown man wants a new birth cert, clothing, or anything else, he will see that he gets it on his own.
If he wants to visit his very evil sister, he will find a reason/excuse to do so.
If he's too vulnerable around his friends/family, then he needed to recognize that on his own, by himself, in counseling, in the rehab center. If he didn't recognize it on his own, he will do whatever he wants to do, including jeaporadizing his sobriety.
What are you doing for yourself to prepare yourself to let him lead and control his own life, and also prepare yourself emotionally for the possibility he may fall off the wagon?