How should a wife deal with her husband who caused a rift between her and his sister by misrepresenting the reason for the wife's refusal of his sister's prolonged stay in their home, and he still blames her for it despite three years having passed and his sister not having visited their home?

A husband should not relay his wife's words to his sister, unless his intention is to cause discord, in which case it is forbidden and constitutes backbiting (namimah). The husband's sister should have verified the information before making a judgment. The issue does not require confrontation or estrangement, but rather a call or a visit to the husband's sister to clarify the viewpoint, appease her, ask for her forgiveness, invite her for a visit, and present a gift.