Your father's grandfather is your ...
great-grandfather
Your sister's daughter is your ...
niece
Your brother's son is your ...
nephew
Your daughter's daughter is your ...
granddaughter
Your father's new wife is your ...
step-mother
You brother's wife is your ...
sister-in-law
Your sisters and brothers are your ...
siblings
You mother's new husband is your ...
step-father
You son't son is your ...
grandson
You sister's husband is your ...
brother-in-law
You uncle's children are your ...
cousins
Your father's sister is your ...
aunt
Your mother's brother is your ...
uncle
You grandmother's mother is your ...
great-grandmother