Sister-in-law's relationship is not good, and I am particularly annoyed when I see them.

Sister-in-law is not related by blood, so there is no feeling that blood is thicker than water, and there is no reason to please each other. More of a competitive relationship, some sisters-in-law for the legacy of their elders, so that they don't really like each other, which is also the difficulty of getting along.

Sister-in-law is the daughter-in-law of this family. In the eyes of others or parents, there will always be good and bad. Where there is contrast, there is competition. Women have a strong vanity, so a little trouble between sisters-in-law will lead to disharmony.