?
I don't think so. You're probably 16 and she's 14? I think it's fine. However, most of the people I know wouldn't date their younger sister's friend just because the friend kind of reminds them of their sister. In their head, their sister is like a baby- even if she's 14- so to date her friend would be weird for them, but if you don't see a problem with it and your sister doesn't and the girl doesn't- I don't think there is anything wrong with you two starting a relationship.
I'd be careful if you're 17 though. Her parents probably won't like that.
maybell
No, I'm a freshman girl dating a junior guy. Just be careful bc of the age difference