Originally, I sincerely thought that the use of the word 'abuse' was too strong of a word, but after reading some comments, I realized the severity of the problem. Truthfully, I often abused my sister, but never in ways as extreme as those stated, usually just manipulating my parents to get what I wanted, at the expense of my sister (for bathing privileges or something similar)
I realize now that the issue at the stem of this problem is the parents and the support that they give their child and their ignorance. With my parents help, my manipulation came to an end when I realized what I was doing wrong.