Your aunt's daughter is your first cousin, as is your aunt's son.
First cousins, twice removed. Aunts daughter is your cousin. Aunts daughters daughter is cousin once removed Aunts daughters daughters daughter is cousin twice removed.
The grandchildren of any of your great uncles and great aunts are your second cousins.
Your aunt's daughter is your first cousin.
the daughter's cousin
yes
Your first cousin.
Yes, although in that relationship there is likely to be a very large age difference, since that person is of the same generation as your grandparents.
Her aunts/uncles daughter.
great nephew
They'd be your cousin.
They are your Uncles and or Aunts.
Your aunts' mother-in-law.