Any man whose brother or sister has a great-great-great-grandchild is a great-great-great-great uncle.For you, he would be your grandfather's grandfather's uncle or grandmother's grandmother's uncle, or any combination of the two relationships.
You grandson is great great nephew to your uncle. You uncle is great great uncle to your grandson
You grandson is great great nephew to your uncle. You uncle is great great uncle to your grandson
Your mother's great great uncle is your great great great uncle
Your great uncle (by dictionary definition) would be your grandparent's brother. His great uncle would be his grandparent's sibling. So it would work out to be your great great great uncle (3rd great uncle).
Your great uncle is the brother of one of your grandparents. If you are a boy, you are your great uncle's great nephew. If you are a girl, you are your great uncle's great niece.
Your uncle is the brother of one of your parents. Your great uncle is the brother of one of your grandparents. Your great great uncle is the brother of one of your great grandparents.
Your grandfather's uncle is your great great uncle. Your grandfather's brother would be your great uncle
He would be your Great Uncle, you would just address him as uncle.
Your mother's father's uncle is your mother's great uncle and your great great uncle.
your great uncle your grandmother's brother is your parent's uncle.... and confusingly enough when your parent is related to someone of the generation older than them (their uncle) it becomes your (great uncle) great relative.
Yes, there are DNA tests that can determine whether a great uncle, or a great aunt, is likely related to a particular child. DNA samples are needed from both the child and the adults whose relationship is to be assessed.