They're related to you
my great grand-daughter
She would be your son's second cousin.
Your niece's son is your great nephew. You are his great aunt (if you are a woman) or his great uncle (if you are a man).
The son of your great niece is your great great nephew. You are his great great uncle.
Your niece's son's daughter is your great grand niece. Your niece's son is your grand nephew or your great nephew, whichever term you prefer.
Your niece's son is your great nephew.He would be your grandnephew
Your granddaughter and your niece's son are second cousins.
Your niece's son is your great nephew. You are his great aunt or great uncle.
You are her grand uncle (or great aunt) and she is your grand niece.
i think its a GRAND niece instead of great niece and u would be a grand uncle or a grand auntie to her
Your daughter-in-law's niece and nephew would be considered your grandchildren's cousins. So, you would be their grandparent-in-law.
You aren't. You do not share a common ancestor.