Usually, I'm pretty good at finding stories, but this one is eluding me. Here's what I remember...

I know I read this on fanfiction.net and I don't believe it was longer than 10k, if that. It was set in the early seasons (no angels). It was gen. Sam was kidnapped by vampires (Kate may have been one of them) and kept caged in a basement. Dean and a group of generic hunters come to the rescue. At one point during the fight, Dean opens the cage, but Sam won't step out of it. Dean says something comforting and understanding about Sam wanting to stay safe. What does drive Sam out is when a very young vamp is about to attack Dean. Sam very violently chops the vamp up. Sam later tells Dean he watched them turn the child in front of him.

Dean helps Sam upstairs and another hunter holds out a container that has the personal effects of the victims (some of which the other hunters were currently putting down since they'd been turned) and Dean grabs Sam's wallet/phone and his bracelet. I think Kate got away.

Any help would be greatly appreciated!

Fic found in comments!