Umm, well they would just be related ?
Great Grand Nephew
Your sister's son is her grandson and your great nephew. Some use the term "grand nephew."
Your sister's son is her grandson and your great nephew. Some use the term "grand nephew."
Your grandson and your great nephew are second cousins to each other.
Your nephew is the son of your sibling and a first cousin of your childrenYour grand nephew (or great nephew) is the grandson of your sibling and a second cousin of your grandsonYour great great nephew (or great grand nephew) is the great grandson of your sibling and is a 2nd cousin once removed of your grandson
Your grandson is your sister's great nephew and she is his great aunt.
Your father's great grandson could be your grandson, or your great nephew.
Yes. Your grand nephew, also called great nephew, is the grandson of your brother or sister.
The son of a great grandson is a great greatgrandson.
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 brother is your grandson's great uncle, and your grandson is your borther's great nephew. Some people would also say grand nephew and grand uncle.