All I can remember from it is that when Connor was kidnapped by Holtz, the kidnapper (for some reason) detoured through Sunnydale. Spike rescued Connor, and can tell from the baby's scent that it must be Angel's son. I'm not sure what the pairing in it was, but I think it was slash.
Vague, I know, but if anyone has any idea which fic it could be, please let me know.
Thanks,
Jen