Family is too picky

There’s this nice potential, we live in the same city, and share the same ethnic background (we’re from the same city back home). My sister is against it because his family comes from a not so good neighborhood back home (the people there are known to be “tacky”) and she’s worried I might have to live there if I ever visit our motherland. I tried convincing her, she said it’s a no. I’m frustrated because he seemed like a good match.