ما هي المسؤولية الدينية تجاه الأخت المقيمة بمفردها في بلد آخر؟

Your responsibility towards your sister is to protect and care for her as much as possible. Her living alone poses many risks. Therefore, we advise you to live with her if you can. Otherwise, look after her by offering advice and reminders, and take the initiative to marry her off if she is not already married.