You were the youngest Winchester. You were not meant to be any kind of vessel, but the one true witness to the apocalypse. And by that you'd remember the fight between Michael and Lucifer and recite it and then be killed by the angels. That is what was supposed to happen, but after the whole stopping the apocalypse thing, the angels allowed you to live.

So, you went about mostly being normal until Sam came around, apparently freed from the cage, and sometimes, you'd just sit and repeat details about the fight Lucifer and Micheal had that ended with them in the cage.

Sam mentioned it to Dean. Sam, over the past year, on account of the soulless thing, har been next to no help, and you'd been scared to bring it up to Cas. Dean watched you you did this, staring off into space as you spoke almost robotically.

"Kid, can you hear me?" Dean asked, as you began repeating yourself again.