User blog comment:Ajrep1994/Yang and Ruby are half sisters/@comment-3146930-20140723223108/@comment-4010415-20140724002428

Let me explain step-sisters and wedlock/illegitimate child.

1. Step-sisters = Ruby has her own mother and father, Yang has her own separate mother and father. Yang's dad marries Ruby's mom. Absolutely no blood relation between Ruby and Yang. Half-sister is where Ruby and Yang have the same, say, dad, but were born from different mothers.

2. Illegitimate child is born out of wedlock. Wedlock is where the parents are married.