Back on Track

I have a 16 year old older brother who is going down the wrong path. He drinks, smokes, curses, hangs out with his wrong friends most of the time and doesn't take his schoolwork seriously. He's repeating 9th grade because he failed two classes last year, but he's still slacking off and getting bad grades. He stays over his friend's house during the weekends and usually doesn't come home until Sunday since he has school on Monday. I tried talking to him and offering to help him with homework, but I really don't know what to do with him. I try to show him love, but sometimes I lose my patience with him. My father is a good person but let’s himself get walked on most of the time, and my brother was feeding off of that. My dad would give into Dave, and give him anything he wanted. New clothes, gadgets, money. My brother's room was also severely dirty; you couldn't even see the floor from all the dirty clothes, and junk. My father did nothing about it and asked Dave time and time again to clean it. Dave would say he would, then nothing would happen. My father kept believing it would get done, but nothing did. It got so bad my father refused to even open Dave's bedroom door to see the mess. My father said it was his room, and if he wanted to live in a dirty room, it was his choice. I never saw it either, considering I didn't live there. But it was my father’s house.Nancy called me up one evening and told me her and my dad went into Dave's room to clean it. In his closet they found more than 70 bottles of vodka. Not those teeny tiny bottles, the jugs. Again, nothing was done about the situation. When my dad would confront Dave, Dave would get severely irritated to the point he would start to shake. So my dad would back off and do nothing.