Watching Winchester's

Castiel is instructed by another angel that he's has to watch over the Winchester brothers. Castiel agrees. But what he didn't know was that the Winchester's were children. He arrives on earth expecting a full grown Dean. Instead, he runs into a five year old Dean. Dean takes Castiel to where he was hiding with Sam. Castiel takes pity on the children and takes them to the bunker, where he raises them. At first, Castiel is frustrated to have to watch over children, but as time goes on, and as they grow older, Castiel learns to love them more and more as each day passes.