That would be her great uncle I suppose. Common sense.
Your brother's daughter is your niece..and you are her AUNT.
Great Niece.
Since your niece is your daughter's first cousin, your grand niece (the daughter of your niece) is your daughter's first cousin, once removed.
my great grand-daughter
Your daughter and your niece are first cousins Your daughter and your great grand niece are first cousins, twice removed.
YES
the boy is a grand nephew 2 me
The relationship between your brother's daughter and your granddaughter is that they are first cousins. This is because your brother's daughter is the child of your sibling, making her a cousin to your child.
You are their aunt or aunt by marriage.
you will be his great great grand son/daughter..:)
They would be cousins, once removed.
First cousins twice removed.