The answer to this riddle is quite simple, although often answered incompletely - I am either your aunt or uncle, one of your parents or your 1st cousin, once removed (one of your parent's cousins).
If your great great grandmothers were sisters, your common ancestors are your great great great grandparents. That makes you 4th cousins.
Your grandmother's sisters are your Great Aunts.
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).
Great neice
Yes, along with your grandfathers' sisters, if any.
Your her great great aunt!
WHAT relationship* is your Gramps to your great granddaughter? pretty tricky but (distant sisters one off)
no problem man! enjoy
The relationship is that of a great great great grand uncle and great great great grand niece
Your great great grandmother's sister's great great grandson is your third cousin, twice removed.
You granddaughter is a great great niece of your aunt. Your aunt is your granddaughter's great great aunt.
Your sisters grandson would be your grandnephew.