It is possible I made this all up in my head. All I remember is that the Winchester's are staying in a dodgy motel or apartment and the mould or dirty water in the bathroom makes Sam sick. Pretty sure the boys were teens. That's all I remember sorry.
Additionally, my favourite fics to read are very similar to this one so I'm asking for any teen sick!sam stories that you know of. A good example is "Slipping Through the Cracks" by Kokoda2007.
Any help would be much appreciated, thanks in advance! :-)