Jarp, I'm sorry it's come to this. I hope he finds his way back to sobriety through the treatment program he's already in; I wonder if his professor sees this as part of the process?
My heart goes out to your little boy who seems wise beyond his years.
Otherwise, you seem to have everything in hand, even though I'm sure it's costing you a lot emotionally.
Trick to the snow; waterproof everything. As I fellow Aussie with limited snow experience, at first I was surprised at how wet snow was.