What is the ruling on obeying a husband who swore he would not enter his wife's family's house except to pick her up, knowing that he did not prevent her from visiting, and is he permitted to act this way, and what is the advice regarding this matter?

Obeying the husband is obligatory as long as he does not command an act of disobedience. This includes the wife not leaving the house without his permission. The husband should not swear an oath not to enter his wife's family's house. He is permitted to break his oath if it does not involve divorce, and he must offer expiation for the oath. You must appreciate your husband's rights and obey him. As for your sister who wrongs you, meet her wrongdoing with kindness and her severance with connection, as Almighty Allah says: "And not equal are the good deed and the bad. Repel [evil] by that which is better; thereupon, suddenly, he to whom between you and him is enmity [will become] as though he was a devoted friend."