She'd be your second cousin; your uncle's daughter would be your first cousin.
You mother's uncle's granddaughter is your second cousin.
Your uncle's granddaughter and your child are second cousins.
Your great uncle's granddaughter is your second cousin.
Your uncle's great granddaughter is your first cousin, twice removed.
. Your uncle is one of your parents brother. His son or daughter is your cousin. The granddaughter is a second cousin.
Your grandmother's brother is your great uncle. Your great uncle's son's great granddaughter is your great uncle's great great granddaughter. Your great uncle's great great granddaughter is your second cousin, twice removed, and is your daughter's third cousin, once removed.
Your grandfather's brother is your great uncle. Your great uncle's daughter's daughter (his granddaughter) is your second cousin.
If she is your biological granddaughter (not step or adopted), yes.
Your granddaughter could be your son's daughter, or your son's niece.
An uncle's nephew and the uncle's child are first cousins to each other. The uncle's great granddaughter and the nephew are first cousins twice removed to each other.
great uncle
Your brother's granddaughter is your great niece and you are her great uncle if you are a man, or her great aunt if you are a woman..