You would call your wife's sister your sister-in-law. If your wife would have a brother he would be your brother-in-law. It is the same thing for a husband's siblings. Your wife's mother would be your mother-in-law. Her father would be father-in-law.
Your sister in law is your husband's sister or your brother's wife.
You would call your wife's elder brother's wife "sister-in-law."
There is no specific word for the husband of your wife's sister. If you need a phrase, call him your "sister-in-law's husband."
My wifes brother in law!
i believe that your brother's wife's sister is also your sister in law No, I think not! But as you seem to have the hots for your brother's wife's sister, you can call her "honey" if you like.
Your wife's brother is your brother-in-law.
Your child would call your sister her aunt.Your sister would call your child her niece or nephew depending on gender.Your sister's children would call your child their cousin.
That would be your cousin, honey. Just keep it simple and call them what they are - family. No need to complicate things with all those fancy terms.
You would call your sister's husband your brother-in-law.
I would not touch this matter unless you are interested in self-destruction.
You would call your mother's sister an aunt.
You would call your sister's daughter your niece.