The accurate title of sister-in-law is menstruation, which is a relative title, referring to the mother's elder sister or younger sister, also called menstruation, also called menstruation for short. Dialect, many places in the north call his wife's sister-in-law; The wife's sister is called eldest sister or elder sister.

Wife's sister, wife's sister, because the child called her aunt, over time, this title was formed. The title corresponding to sister-in-law is brother-in-law People usually say that brother-in-law and sister-in-law are of the same generation and have close ties, so they don't have to stick to formality and seriousness. Northeast custom, this relationship can be called a joke, but if it is the brother-in-law and sister-in-law of the closest relatives, joking must be measured, enough is enough, and not too much.

In the same way, call his wife's sister big sister, because the children call her big sister. This is a feature of dialect formation. The corresponding title of eldest sister-in-law is brother-in-law. This relationship is serious. Don't joke, you must respect each other, and you can't be contemptuous or funny.

@ also refers to women of the same generation and age as their mothers.

It seems that the relationship is not necessarily, hehe.

There are nurses, and the relationship is not necessarily.

@ Some places refer to stepmother. Well, the relationship with my father should be husband and wife.