I need serious help from any Cristian's, former drug addicts or rehabilitation experts?

ok so i am 14 years old and the youngest of the fam my 2 older sisters are 29 and 23 and my older brother is 21. me and my older brother are incredibly close its almost too hard to explain, every single thing that happens to him i know and everything that happens to me he knows. my whole family is healthy an christian but it seems like i have the most faith then anybody everybody else is so frustrated with him all they can think about is the negative things about him while i embrace the positive side of him. my brother smokes marijuana about every single day 3 or more times along with him oxy cotin addiction im not totally sure how long he has been addicted but if i had to guess i would say no more then 2 years and almost positive not this long. he and my mom just had a fight and he moved out with his dad but this probably wont help much because unfortunately hes father is afraid of him only because hes an amazing fighter ha ha. i prey every single night for him and during the day but it doesn't seem like anything is getting better, i really do not know what to do anymore and neither does my family luckily im the only one with hope strong as metal for him so i keep my family faithful. all i am asking is for ideas and other thing that would be great help for me, thank you and god bless.