Board Thread:Speculation House/@comment-9058532-20130807182204/@comment-120.149.34.2-20140525143807

Personally, I feel that Cinder is a bit older than to be Yang's Sister, with her relations to Roman and so on. Could she possibly be Yang's original mother?

Mr. Xiao Long and Cinder created Yang, Mr. Rose and Summer Rose created Ruby,

A chaotic event (fire dust explosion?) causes Yang and Cinder to both gain a semblance for fire, and while in the chaos Yang stays with her father, Cinder leaves for her own reasons,

Mr. Rose dies for some reason, there are many events which this could be related to,

Mr. Xiao Long and Summer Rose get together, causing Ruby and Yang to become sisters,

Summer Rose dies, in reference to the songs and the gravestone. 'White Cloak' is likely Ruby's memory of her.

This is all a theory of course, but I haven't encountered any information against this so far.