Drug addict brother, HELPPP!!!!!!!!!!!!!?

Im 13 years old and live with my parents and my 2 brothers, one a 20 year old drug addict. My brother has been using for the past year and a half( feels like forever to me ). Even though he is 20 my parents pay him 50 euro every week. Which i find very unfair because shouldn't he be paying them rent? Anyway, my parents bring him to drug councellors, phsychologists everything but nothing works. My parents are trying to pay off his debt at the moment for him which doesnt work because he goes back to his drug dealer and gets more 'stuff ' on tab, meaning he pays them later, or rather my parents. He is growing cannibis in my attic which my parents are fully aware of, and smokes weed and does drugs frequently in the house. He is also stealing, he owes me 500 euro from my savings which he stole. I'de say if you added up how much he owed my parents it would come to about 10,000euro. Everytime i say anything to my parents they tell me to shut up hes going through a tough time and that hes their precious son. I am left on the side and they seem to forget they have 2 other kids. I honestly feel very depressed and my parents really really dont listen to me. I have asked them time and time again to kick him out but they won't because like i said hes there precious son. I am getting so fed up of this and cannot wait another 5 years to move out of the house. I have no clue what to do but believe i shouldn't have to deal with this. Maybe im being dramatic but this has turned into a living hell for me.