Your father's niece is your...
Cousin
Your uncle's son is your mother's...
Nephew
Your cousin's aunt is your...
Mother or aunt
You are your mother's...
Son or daughter
Your brother's father is your...
Father
Your father's brother is your...
Uncle
Your cousin's mother is your...
Aunt
The daughter of your father is your aunt's...
Niece
The mother of Maria's father is Maria's ...
Grandmother
Your aunt's father is your...
Grandfather