Thats terrible, and it is the harshest way for your nephew to learn.
I know its not the same thing, but it opened my eyes and opened the eyes to the right people,

My Aunty had always had back issues, always in mega pain, she started off on Panadol, then Nurofen, she then seperated from my Uncle (for other reasons) and shortly after fell pg with another guy (whom she was planning on leaving), Although she never told anyone(they never do) it became blantely obvious she was using, wearing long sleeved drugy shirts to cover the marks and other various symptoms. In the end it became to much for her and she took her own life.
She left behind 6 kids, ranging from 30 to her little boy only approx 6months and a huge group of family and friends. It was hard to deal with, but one of her daughters (she had 3 of them) who was around 23 when her mum died, was also believd to b using. It was like a slap in the face to her and snapped her out of the world she called her own and was, fortunately, welcomed warmly back into ours. She continues to do well.

Im sure your nephew will do the same thing, snap out of any thought of using anything, and prob even become a spokesperson for his mates if they use or are contemplating it.

I wish there were more people like you around, then we would all have someone who loved and cared about us to turn to, when in need.

Godbless all of you