Your husband's third cousin is just considered your third cousin through marriage.
Your husband's cousin's sister is also your husband's cousin. You are not related to your husband's cousin.
Cousin in Law
Cousin through marriage.
The common house cat is considered to the domestic cousin of the tiger. Cats are also considered to be the cousin of lions as well.
I think that you call them your cousin in law because its pretty much the same concept as a sister in law... its your husbands cousin so it would be a cousin in law
Your cousin in law
Only you hold the key to why you had an affair with your husband's cousin. It's called cheating for one.
Yeah, but it would be a little weird
Your parent would be a first cousin. She would be your husbands first cousin once removed.
He/She would be considered your second cousin.