User blog comment:Endor 66/Why do Ruby and Yang have different last names/@comment-24342832-20140227074854/@comment-3146930-20140227224357

It wasn't really a joke. It was more of a shout-out to RvB. However that would be interesting. Going by the lyrics to Red Like Roses II, the person singing from [presumably] the perspective of Ruby's mother says that she made a sacrifice, which resulted in an even bigger sacrifice Ruby will have to make. It could be that Ruby's bloodline has some kind of special trait that is needed to complete a ceremony that requires a sacrifice. This trait is identified by silver eyes, explaining why Ozpin was surprised by them. Maybe this is why Weiss' Glyph turned red when they were attacking the Nevermore. Until then, Weiss' Glyphs had only been shown Pushing (blue-ish color) or Pulling (Black color) objects. Maybe Ruby is able to amplify certain Glyphs when in contact with them.

Anyway, going back to the song. It sounds like Summer hadn't intended to die at all as she planned on seeing Ruby when she made it home again. This could be flipped around however, meaning that Summer got home and Ruby was missing after leaving her at home by herself. If that is true, maybe she went out looking for her and found Ruby at the place where said ritual needed to be done to keep some all powerful being asleep. With Ruby there, it began to wake up and Summer was forced to perform the ritual in haste to save Ruby, causing her to die in front of Ruby and the ritual itself wasn't done right, forcing Ruby to perform it later in her life, but with a much greater cost.

"What does this have to do with Yang and Ruby having different names?" you might be asking. Well, nothing. I don't no, maybe Ruby just decided to keep her mom's name.