Her grand great Aunt.
Presuming your son is also your wife's son, the your wife's aunt is your son's great aunt and he is is her great nephew.
The son of your aunt and uncle is your first cousin.
Your niece's son is your great nephew. You are his great aunt or great uncle.
If you are female and have a son, your aunt's niece's son could be you. Your aunt's niece's son could also be your first cousin, once removed, if he is the son of one of your first cousins. Your aunt also may have nieces who are not related to you, and then the son is not related to you either.
Your niece's son is your grand nephew, and you are his great aunt.
I'd normally call him by his first name. And the son of your aunt is your first cousin.
The name given to the son of your aunt is first cousin or simply cousin.
a nephew's kid to his aunt's kids would be their cousin.
Your aunt's child, son or daughter, is your First Cousin. The same is true for your uncle's children.
Where is aunt esther
Her grand great Aunt.
Your aunt's son and her niece are first cousins to each other.