I wouldnt think twice about it, I mean a brother or sister, Im supposed to love them like I love myself, I mean you might always get wisphers and get scared but the right thing to do would be to help.
Plus I m thinking about if I saw a bro or sis being beaten up or something like that, as for personal family stuff, I wudnt knowwhat to do, but if it was a street thing and I was there I would help all out, even if I'd be scared, which I prolly would be.
But then again it would be hard to think if I'd be helping at all, I mean in the news here a brother got killed and then in the case one of the defendents said that him and his 'gang' were trying to force people to convert, but i know all of those guys and they wudnt do that, but its just an escuse.
anyhow, yes, inshaAllah, because that bro or sis is my bro or sis and i dont want them hurt.