Eldest brother and sister-in-law often quarrel, but this quarrel is very serious. How can I comfort my sister-in-law?

You haven't come to the door yet, so you'd better not make any comments. Listen.

Don't mind the quarrel between husband and wife, because you can't manage it well. If they make up later, what your sister-in-law said to you today will become what your sister-in-law said to you later; If they don't make up, maybe she will think that you didn't do well and didn't really help her. Unless you are their parents, you can say anything. You should understand that the quarrel between husband and wife is between the head of the bed and the end of the bed. How many women have been abused and cried for divorce, but they really went to the Civil Affairs Bureau. Most of them don't want to, and they just want to vent on you.

Besides, you are going to marry into their family in the future. If you don't say a word right, many things will happen for no reason.

In this case, just ask her what to do and whine.