If your great uncle is the brother of one of your grandparents, his wife is your great aunt but their nephews and nieces onher side are not related to you. Those nieces and nephews (and their children the great nieces and great nephews) have no ancestor who is also one of yourancestors.
Your father's uncle's uncle is the son of your great great grandfather. He may be your great grandfather or he may be another brother of your great grandfather, and thus your great great uncle.Your father's uncle also has aunts and uncles from the other side of his family. That is, he has uncles who are brothers of that one of his parents who is not a descendant of your great great grandfather. Those uncles are not related to you at all.
You are related "by blood" to anyone who is descended from someone you are also descended from. That includes your great grandfather and great grandmother and all their children, grandchildren and great grandchildren.
Your nephew's son is your great nephew and you are his great aunt or great uncle.
The son or daughter of one of your siblings children is your great niece or great nephew. In other words, the grandson or granddaughter of your brother or sister is your great niece or great nephew.
The child of your nephew is your great nephew (if a son) or your great niece (if a daughter).
not to be complicated , but if you have an uncle--> he has a nephew--> as you can see that's not complicated . And if you ask what is a uncles NEPHEW related to an uncles grandfather. in what way ....i would say the nephew is is the great gandfathers great grandson.
Your uncle is your child's great uncle and your grandchild's great great uncle. Your grandson is your uncles great great nephew.
I believe they would be great aunts or great uncles.
If your great uncle married into your family some of his nieces and nephews are your aunts or uncles (or your parent) and some are not related to you at all.
Your aunt is your child's Great Aunt, so your child is her great niece or great nephew.
Your nephew's son isyour great nephew. You are his great aunt or great uncle.
You are your great nephew's great aunt if you are a woman, or his great uncle if you are a man.
Your nephew's daughter's son is your great grand nephew (or great great nephew). You are his great great aunt if you are a woman, or his great great uncle if you are a man.
A great uncle is the brother of the great nephew's grandfather or grandmother.
Your father's uncle's uncle is the son of your great great grandfather. He may be your great grandfather or he may be another brother of your great grandfather, and thus your great great uncle.Your father's uncle also has aunts and uncles from the other side of his family. That is, he has uncles who are brothers of that one of his parents who is not a descendant of your great great grandfather. Those uncles are not related to you at all.
Your nephew's daughter is your great niece. Her son is your great great nephew. You are his great great aunt (if you are a woman) or his great great uncle (if you are a man).
In English language terms for family relationships, there is no relationship called "nephew once removed." The son of your nephew is your great nephew.