There is more than one day I count as the worst in my life, killing Karen, not saving Dean from hell and today—letting Sam fall to Lucifer's cage – that poor boy – also the day the boys were bound to those angels.
Dean blames himself. The apocalypse is too big for one young man to take one himself, but he does. This whole thing was set in motion, as best as I can tell, long before the boys were born; and it's not fair, not just to Sam, but really not to Dean.
When they were kids I left them alone, John was there, but that was more than alone—I left Dean in charge, and he may have been ten, probably nine. Dean would never refuse Sammy anything. Dean loves his brother; fool went to hell for Sam. That one summer afternoon I went to the store, and, as Dean told me, they went to play in my office; they had been forbidden, but they were boys, I should have expected something of the sort. Somehow, and Dean was never clear, they ended up setting up a ritual for calling Angels…just for fun. Sam has been much clearer, he says it's on him, he made Dean do it, and Dean was just along for the ride. But, however it happened, I - like the fool Rufus says I am - went to the store and left the boys in the care of John. John, drunk that he was, ignored those boys, and fell asleep on the couch—out for the count.
I came home—I was still parking the old van when I heard Sam chanting. Damned if that little boy, didn't get his tongue around Enochian like it was easy. Then I realized what he was doing. I cursed at the boys—and I regret that, they were children; they had no idea what they were doing. Then I ran, I called to John – waste of my time – and ran to those boys as fast as I could. I didn't clearly recall the Angel to whom Dean was bound, Castiel, more than familiar today; but Sam…Lucifer…Sammy, did you have to choose Lucifer? Now I wonder if it was the demon blood in Sam that pushed him to that choice; we didn't know about the demon blood then. Dean says that it is his, Dean's, fault, Sam wanted to share Cas—and Dean wouldn't let him. Sam still looks like he wants to share Cas. Running into the room as Dean blew out those candles, that was the day my world ended—that spell was a binding, precious little Sam belonged to Lucifer—and Dean would never forgive himself. It wasn't Dean's fault, never was; he had no idea what he was doing—it was fate in a way. I wonder though, if I hadn't left those boys alone if it would have happened at all; if they could just have been hunters, lived hard lives, but not this, not hell for both my boys. I wish I could hold them both one more time, as close as I did that afternoon; they're still both boys.
John lived his own hell; that's about all I can give him. He didn't bother with those kids, not that afternoon, not any afternoon. I told him that day that if anything, anything happened to either of those boys, nearly happened to those boys, I would take them from him. I guess he took me seriously, shot-guns help folks take things seriously, he cleaned up his act. It was too damn late though.
And tonight Sammy jumps into the pit to save the world because no one watched those boys.