If your sister marries someone else's brother, that brother is your brother-in-law (and you are his brother-in-law or sister-in-law), but you are not related to that someone else.
Yes.
No.
Real sister, half sister, or step sister
There are two ways your father's only brother can have a sister-in-law.If the brother marries someone who has a sister, that sister is his sister-in-law and is not related to you.The other sister-in-law he can have is the wife of his brother, i.e. your father's wife, also known as your mother.
There is no name for such a person, because there is no relation. Example. Bob and Susie are brother/sister. Susie marries Tom. Bob and Tom are Brother's in law. Bob has NO relation to anyone else in Tom's family. Susie does however.
Theoretically, your sister.If your sister marries, her husband is now your brother in law. So his wife would be your sister. If he has re-married, he is technically not your brother in law anymore, so you have no direct relation to his wife.AnswerYour brother-in-law's wife is your sister-in-law. That is to say your wife's brother.
The sister's son would be the nephew of her brother.
No. The sister is a relation, and her husband is an in-law. The husband's brother is no biological relation either. Therefore, the great granddaughter of the husband's brother is not a relation.
No relation
Your fiance's sister is not related to your brother or sister. However, once you are married and your fiance is your wife, she will be their sister-in-law and they will be her brother-in-law and sister-in-law.
Your brother's wife is called your "sister-in-law." If you are a male, you are her brother-in-law and if you are female, you are her sister-in-law.
If your sister-in-law is the sister of your spouse, her brother is your brother-in-law (or your husband if you are a woman).If your sister-in-law is the wife of your brother, then her brother is not related to you.