User blog comment:Doctor Rivers/Why Yang's Hair is Important to her Theory/@comment-4023909-20151115000154

its been shown already that raven is Yangs mom.. its shown in Crows team picture in the seasons opening (http://rwby.wikia.com/wiki/File:V3_Opening_00029.png)

and yang gets pissed when anything happens to het hair, making her semblance go hyper. it may be caz her powers in her hair, so if something happens to it, it goes crazy (or she just doesn't like people/gimm/anything messing with her hair)