Am I obligated to bid farewell to my husband's sister in person before 'Umrah, or is a phone call sufficient, especially after a previous incident between us involving her daughter stealing my bracelet and her ill-treatment of me, along with my husband's request for me to visit her?

It is not obligatory to bid farewell to the wife's sister, whether there is a dispute or not. However, bidding her farewell is preferable and can be done through a phone call or a visit. If the husband commands her to bid farewell to his wife's sister directly, then she must obey him, unless it causes her hardship, due to the positive impact it has in reconciliation and comforting the husband. We advise wise individuals to intervene to reconcile between the two parties due to the great reward in doing so, as Islamic law aims to foster love and harmony among Muslims and prohibits estrangement without a valid reason.