Board Thread:General Discussion/@comment-87.102.2.235-20160720090052/@comment-26397825-20161201113303

The creator knows the truth...and has explicitly told us Ruby and Yang are half sisters before they even revealed who the parents were.

Qrow is not related to Ruby in any way except as a loving adopted uncle. Taiyang is the father of both girls, Summer is Ruby's mother, and Raven is Yang's mother. You can care about someone and not be related to them, you know.