harry potter lives with his family- they dont have the family name because that comes from his father- who as far as we no so far, does not have any more family left!
I know. But they never say anythig abut his Potter family. I mean, the reason Dumbledore gave Harry to the Dersleys was because of his mother saving him (stuff like that). So maybe he does have some live other relative.
harry doesn't have any living family. jk said in a web chat ages ago, i can't remeber wahat she said exactly but she basically said that harry's grandparents on both sides were dead and that will will find out a little about his family past but its not essential to the plot
yeah...Stone17 is right. Petunia is the one that shares his and his mother's blood. I dunno wat happened to Harry's grandparents (tho I spose JKR will reveal something about that in the 6th book) but I think they probly died cause they would have shared Lily and Harry's blood 2. Plus Dumbledore said somewhere in the books that Harry had no living relatives other then Petunia.