Familia...

So, here we go.
My mother (who we will be calling Sue) is a hispanic woman, married currently to a white man named (Duncan). I have 3 sisters, but they're only half. (Casey) is my father's child, but not my mother's. She has a different mother. (Erica) and (Haley) are my mother's children, but not my father's. I am the only child between both Sue and Duncan.
There we go.