(1) Your father's 1st cousin is your 1st cousin once removed.
(2) His son or daughter are your 2nd cousins.
(3) His grandchildren are your 2nd cousins, once removed.
(4) His great granddaughter is your second cousin, twice removed.
Your her great great aunt!
Your sisters grandson would be your grandnephew.
Your mothers sisters Granddaughter is your second cousin
Your granddaughter and your sister's grandson are second cousins.
Your mothers sisters Granddaughter is your second cousin
Great neice
Your grand-niece.
Yes
granddaughter
Your son and your sisters child are first cousins. The granddaughter is out of synch by a generation. That will make them first cousins once removed.
Well she was the daughter of Phorcys and Ceto, thus making her Gaea's granddaughter. Her sister's were Euryale and Sthenno. The Graea were also her sisters.
Your sister's granddaughter is your great niece and you are her great aunt (if you are a woman) or great uncle (if you are a man).