> Okay, I've been asked about the religious sense I was referring to, so I'll explain that here, since I don't know who else might not understand.
>
> People in some religions consider fellow adherents to be brothers and sisters, regardless of blood relation. That's all.
>
> Nyperold

I was kind of assuming you meant monks, nuns, or other people who might have "brother" or "sister" as a religious title...