Board Thread:Speculation House/@comment-108.69.217.22-20160216061533/@comment-1839918-20160416211538

Ruby was with Yang while they were children on a search for Raven, when Qrow had to save them. Unless we pass it off as Ruby being too young to understand what was happening, she'd have to know by now, especially with how obsessed Yang is with it.

But I doubt she cares at all. In her eyes, Yang would be her sister no matter what. After all, if she knew this, she'd know that Qrow isn't really her uncle, but that doesn't seem to impact their relationship at all.