her 7th cousin.
Your aunt's daughter is your first cousin.
She would be your 2nd cousin.
It would be a second cousin.
The relation of the mother;s sister to daughter is niece-aunts.
Your daughter and your first cousin are first cousins, once removed.
your uncles daughter would be your cousin
3rd cousin I think:-)
Your first cousin.
Your wife's first cousin's daughter is your wife's first cousin, once removed, but is not related to you.
3rd cousin I think:-)
2nd cousin once removed
Your daughter and your third cousin are third cousins once removed to each other.