Sayyiduna Dhu'ayb (may Allah be pleased with him) said that when the time of the Prophet's (peace and blessings be upon him) death drew near, Sayyidah Safiyyah (may Allah be pleased with her) said: "O Messenger of Allah, each of your wives has a family to whom she can turn, but you have exiled my family. If something happens, to whom shall I turn?" He (peace and blessings be upon him) said: "To Ali bin Abi Talib (may Allah be pleased with him)."
Hadith Referenceالمعجم الكبير للطبراني / باب الذال / 4199