Board Thread:Speculation House/@comment-24.247.91.107-20140511154823/@comment-3257939-20150727094904

The question is, Kunrin, why did the girls think he was their uncle?

Qrow Branwen. Not Xiao Long, not Rose. In other words, no biological relation to the family, or at least, not one that the girls know of.

"Uncle by familiarity" would explain it though. How did Qrow realize that Ruby and Yang left their house? He probably entered the house only to find it empty. This could mean that Qrow is simply a close friend of Taiyang in the girls' eyes and he regulary paid a visit to check on his friend who had lost his wife and shut down.