Sam has settled against the wall, keeping vigilant watch over his brother. Stroking his hand through his hair almost absently – an action John knows would never be tolerated if the older Winchester were conscious. Even though the words aren't meant for him, John hears Sam alternating between berating his brother for his "goddamn stupidity" and pleading with him to take better care of himself and his body.

John himself has settled in his usual armchair, eyes trained on Sherlock. Watching his chest rise and fall - albeit a little too slowly – was comforting. He can't help but blame himself for the turn of events. Why didn't I notice it was a danger night? How didn't I even know there were drugs in the flat. I'm his best friend and a doctor for Christ's sakes. Why Sherlock? Why? Why?

John finally breaks the silence that has settled over the flat since their companions passed out in their respective places. "I'm so sorry Sam. I didn't think he would ever do this. It's not like him to talk to anyone. Let alone to offer them his goddamn illegal drugs."

"yeah, well, I'm not sure 'illegal' means much to either of them"

John snorts.

He gets up to make them both a cup of tea, speaking over his shoulder as he works. "I'm still sorry though Sam. Sherlock, he… he's had problems for years. I should have watched closer. Been more vigilant. I thought we were passed all this. And I never thought he would drag dean into his addiction"

Sam sighs. "it's not your fault John. Dean's been treading the slippery slope for years. Drowning his sorrows in women and alcohol and violence. It was only a matter of time until it came to this." I should have been the one who saw it coming he thinks to himself, I should have been the one to stop this foolishness, not John.

He nods his thanks as John hands him a fresh brewed cup of tea. Taking a sip, he continues, "In fact, the only reason he's probably been clean up til now is lack of access. If it was in front of him, he would have been shooting up years ago."

John just nods silently, offering comfort in his silent presence. As the silence drags on, they both settle in as comfortably as possible to watch over their respective charges.

I am going to post chapter 5 now as well. Feedback is always welcome (positive or negative)