Board Thread:Speculation House/@comment-24.247.91.107-20140511154823/@comment-3257939-20140905033431

And don't forget that it resembles the one the guy was wearing in the Dust episode of World of Remnant.

I'm so happy that I got it right: Ruby and Yang are half-sisters. They share a father but have different mothers. Right after Yang was born, her mother went missing and that is the woman Yang was looking for. Right after that, her father married Summer and they had Ruby. Summer went missing and now both girls have no mothers. Yep! Best episode ever!