Your mother's first cousin is your first cousin, once removed.
Your cousin. You are that person's second cousin.
The relation of the mother;s sister to daughter is niece-aunts.
I think they are you cousins once removed
Your cousin's cousin is no relation to you.
If your mother's cousin is her first cousin (if one of each of their parents were siblings) then that cousin is your 'first cousin once removed'. If that cousin has any children, they are your second cousins.
Your mother's first cousin is your first cousin once removed.
Your mother's first cousin is your first cousin, once removed
The child of your first cousin is your first cousin, once removed.
The wife of your first cousin is not related to you.
Your mother's first cousin is YOUR first cousin, once removed. The child of your mother's first cousin is YOUR second cousin.
Your Aunt's first cousin may be your second cousin, onve removed or may be no relation to you at all.
Your Aunt's first cousin may be your second cousin, onve removed or may be no relation to you at all.