Your father's niece is your first cousin, and her daughter is your first cousin, once removed.
I'm pretty sure it's a great uncle.
Grand niece.
my cousons sisters boyfriens dads nieces grandma's favorite sons dogwalkers mothers friends mum twice removed uncles daughter
Great-niece.
your 2nd niece...!
Your daughter and your niece's child are 1st cousins once removed.
My niece's daughter is my great niece.
No he did not. I am one of his grand nieces. He had one daughter.
They are 2nd cousins.
A cousin.
Your niece's daughter is your grand niece, or, as some would say, your great niece.
your 2nd niece...!
Your niece's daughter is your great niece. You are her great aunt or great uncle, depending on your sex.