Board Thread:Speculation House/@comment-24119615-20141123041901/@comment-4010415-20141125190521

Everfew wrote: Yang was looking for her mother, not Raven. She didn't know who Raven was, at the time. Don't you think Raven is Yang's mother?

Especially since Raven's last name is Branwen, and in 2013, a user called Montyoum edited the Qrow page to say Qrow's last name is Branwen. Qrow is referred to as Ruby and Yang's uncle, and since we know Ruby's mother is named Summer Rose, that just leaves Raven as Yang's mother, most likely Qrow's sister.