DUDE! what r u 80!? Sister, is like the latest slang to call girls. Like have you ever heard boys been called bro? Well in case you haven't noticed that is short for brother. It's cool Maybe because in there eyes God created all of us, and that would technically make us all brothers and sisters
no they are not related they are very close friends with each other and call each other sister and brother.
Your father-in-law's sister is your spouse's aunt but is not related to her. Call her by her name.
The mother of your sister's husband is your sister's mother-in-law. The English language has no specific term for a family relationship with your sister's mother-in-law, and you are not considered to be related to each other.
The half-sister of your granddaughter's half-sister is your granddaughter, or is not related to you.
It Is If There Related
The mother of your sister's husband is your sister's mother-in-law. The English language has no specific term for a family relationship with your sister's mother-in-law, and you are not considered to be related to each other.
Your husband's sister is your sister-in-law. Her husband is your husband's brother-in-law. But your sister-in-law's husband is not related to you.
Your mother's sister's husband is your uncle, but his mother is not related to you.
Your husband's sister is your sister-in-law. Her husband is your husband's brother-in-law. But your sister-in-law's husband is not related to you.
Even thought you not related in genealogy sense you are related by marriage and you can say they are newphew and nieces in law.
Your sister's husband is your brother-in-law but English has no term for his sister's relationship to you. The dominant cultures of Europe and North America do not consider your sister's husband's sister to be related to you. The closest you can som is to call her you "brother-in-law's sister."
The English language has no term for a relationship between you and your husband's sister's husband. Most people would not consider her to be related to you. You could call her your sister-in-law's husband.