Dean has a necklace because one of them had to. I was thinking to myself, Ben or Alec wouldn't be likely to give it to the other. I figured that was still a Sam thing. And if you're wondering how Sam got the necklace, I think it goes something like this: Cas goes to Bobby looking for God, so he takes the amulet. Cas gives up on God and throws it away somewhere. Someone picks it out of the trash because it looks valuable. Sam stumbles across it, then gives it to Dean.

As for Sam's height, I drew him in first, realised I'd left no room for Dean, then couldn't be bothered to fix it. *is lazy*

Although I was considering that Sam might be an X6, since the age difference works that way... and my lack of decisiveness is why I can't actually write this thing.