I vaguely remember this multiple crossover with Supernatural and Buffy the Vampire Slayer dealing with the apocalypse in Sunnydale, and she writes to her family members-- hence the crossover-- dealing with Smallville, X-Men, Dukes of Hazzard, Harry Potter, Highlander (I think since Immortals were mentioned) Charmed (?), and possibly Stargate: Atlantis or something similar. The Winchesters weren't related to her, though, and decided to join along, and I actually remember Giles and everybody else kicking Buffy out of the house and they regretted that choice because of the army (literally, an army, this was a big crossover.) that came to help her?

I know that crossovers aren't everybody's cup of tea, but if you know what I'm talking about, the help would be deeply appreciated. Thanks in advance.

Really, thanks in advance.

FOUND; Family Reunions by texaswookie!