Buffy gets pregnant and her parents send her to live with Giles and his son Spike.

Hi lookin for a fic were buffy got pregnant an her parents were ashamed off her so after she has the baby she's sent to live with giles an his son spike an I think she tells spike the baby is not hers but a relative but he finds it odd how she acts with him any help please

I'm sure there are a lot of stories that could fit the describtion - I know of one:

Child of Mine by spikesbabyblues
Summary: Based on Idea in the Idea Factory. Living in LA, Buffy a rich girl (16-17) who doesn't play by daddy's rules...falling for a boy (18-19) from the wrong side of the tracks (Angel?) and getting pregnant after having the baby "daddy" sends her and her baby to live with Mr. Giles in Sunny-dale. Buffy swore to her mother she would keep the fact the baby is hers a secret...so when Spike, Giles's son, starts getting suspicious of the mysterious beautiful girl and the baby boy living at his house and she won't tell him what's going on...problems arise...then Hank shows up with the "per-fect" guy for buffy causing even more wackiness for b/s.... then when b/s finally get together Angel shows up demanding to see his son.... Spike's is crushed...Can Buffy and Spike overcome all the lies and obstacles and get together? )
Could that be the one you're looking for?

I even found a link now - she had her stories here @ TSR but took them down and her site is gone - this one seems to be the same person:

http://www.fanfiction.net/s/1882592/1/bChild_b_of_bMine_b

Yes that's it fanx so much