Im pretty sure its proably a 2nd grandson.
Your daughter's grandfather's brother's son is her mother's or father's first cousin and her first cousin, once removed.
My great great second, half, brother in law who's great great grandfathers....son.
Your grandfathers brother to you is your Great Uncle!
Your grandfather's brother is your great uncle.
cousin
yes
3rd cousin
You would be second cousins.
This is true.
Your grandfather's niece is a first cousin of one of your parents. Her son is your second cousin.
Yes, your grandfather's granddaughter could be your sister, making her son your nephew.
He would be your great great uncle, but you could call him whatever endearing name you both prefer. my great grandfathers brother or my great uncle