One of my google searches lead to me to this thread:
It was something I wanted to ask and comment myself on but the thread is locked now. I asked Moo if I could reask it so here it goes XD
For me "Sissy" was used as a derogatory term to used to mock me when I was younger. So I like little girl better because I would like to be viewed as a girl, not being a 'weak' guy.
Now that I am MtF transgender I ended up using sissy to be short for sister. Some of my close online friends call me sissy for this meaning. That is the only time I really accept it.