I was re-reading kellifer_fic 's story Snuffleupagus And now I'm wondering if there are more fics like that out there.

With Sam having an imaginary friend or with Dean imagining Sam because he's lonely, feverish or because he's crazy? Sam don't have to be imaginary, he can be a ghost, or a demon,perhaps some sort of fey/fairy, maybe inter-dimensional being or an alien?
As long as it's only Dean who can see him at first? I would love it if it was Wee!boys, like in Snuffleupaus but all recs are welcome be it slash or gen.

Thank you all in advance! <3

Edit - Thanks for all the recs guys! They were great!