Your mother's husband is your father. His father-in-law is your mother's father, your grandfather. Your grandfather's son is your mother's brother, and your uncle. Your uncle's daughter is your first cousin.
Your mother's new husband is your step-father and you are his step-son or step-daughter.
Your father's brother's son's daughter is your second cousin.
Mother's grandson as regards her daughter is either her (daughter's) son or her (daughter's) nephew.
Your grandfather's son is either your father or your uncle. Your daughter's grandfather is your father. or your father-in-law.So your daughter's grandfather is your grandfather's son or a brother if there is more tha one son, or, as your father-in-law, is not related to your grandfather's son at all.
The son, or daughter, of your father's first cousin is your 2nd cousin. The son, or daughter, of your father's second cousins is your third cousin. The son, or daughter, of your father's third cousin is your fourth cousin. And so on.
Mothers sister is aunt and son is cousin so daughter wouldn't that be a niece
It could be your father. Your niece's daughter's grandmother is your aunt. Her brother's son's father is either your father or your uncle.
Your father's sister is you aunt. Her son is your first cousin. Her son's daughter (her granddaughter) is your first cousin, once removed.