Your Great-Uncle is your father's uncle or your mother's uncle. Another way to look at it is to realize that your great uncle is the brother of one of your grandparents.
He would be your paternal great grandfather
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 uncles daughter would be your cousin
Your father's brother's son is your first cousin. Your father's brother's grandson is your first cousin, once removed.
Your aunt's great uncle's father is her great grandfather, or is not related to her at all if the great uncle married a sister of her grandfather).He would then be your great great grandfather - or not related to you at all.
Your grandfather's brother is your great uncle (some would say your grand uncle). You are his great niece (if you are a girl) or his great nephew (if you are a boy).
Your grandfather's sister is your great aunt.
Your grandfather's brothers would be the uncles of your parent. That would make them your great uncle.
Your grandfather's father is your great grandfather.
I believe they would be great aunts or great uncles.
That person would be either me or my sister...if the cousin of me great uncle was my great grandfather. If the cousin was another of my great uncles, then the person would be my cousin. Example 1: My dad has a brother who is my uncle. That uncle has a father who is my great uncle. If his father or mother had sisters or brothers who had kids, these kids would be cousins to this great uncle. one of them could be my grandfather. so my grandfather's granddaughter would be me if I am a girl or my sister if I am a boy. Example 2: In any level of the family tree there can be cousins...children of my uncle or aunt. when they have kids they are second cousins...children of first cousins. If these second cousins have kids, they all are third cousins. So since my great uncle had a cousin which was 2 generations above me...the next generation would be second cousins and the third generation would be third cousins. If my grandfather was not the cousin in question, then the cousin would be someone else on the same generation level, 2 levels above me and the granddaughter would be on my level and therefore my third cousin.
It could be your grandfather. Or it would be a great uncle.