Your great-grandmother's sister's grandson is your second cousin once removed.
that would be third cousin
Your sister's great grandson is your great great nephew. You are his great great uncle, or great great aunt.
He would be your great-great uncle.
The grandson of your nephew is your great great nephew, but few people use that relationship as a form of address. Usually they call relatives by name or business title, not by relationship.
Babur was descended from Tamerlane (Timur). He was his great-great-great-grandson.
At most, each person has: 1 Father 2 Grandfathers 4 Great-grandfathers 8 Great-great-grandfathers - etc. If there have been marriages between cousins, the number of individual ancestors may be reduced as one person fits tow or more places on the family tree.
Your great great grandmother's sister's great great grandson is your third cousin, twice removed.
Yes, along with your grandfathers' sisters, if any.
You Aunt is you grandson's Great-Great Aunt. Your grandson is your Aunt's Great-Great Nephew.
Your brother is a great great uncle to your great grandson. Your great grandson is your brother's great great nephew.
Your sister is your grandson's great aunt. He is her great nephew.
Your great aunt's grandson is your second cousin.
Your sister's great grandson is your great great nephew. You are his great great uncle, or great great aunt.
She would be your great grandmother
Your niece's grandson is are your great-grandnephew.
Your great grandmother's brother's great grandson is your third cousin.
Your great aunt's great grandson is your second cousin, once removed.
He would be your great-great uncle.