Sayyiduna A'idh bin Amr (may Allah be pleased with him) narrates: I took part in a military expedition with the Prophet (peace and blessings be upon him). When we were returning, the wife of a man began to weep; that man had taken part in the battle with the Prophet (peace and blessings be upon him) and had attained martyrdom. The Prophet (peace and blessings be upon him) asked: "Who is this weeping woman?" He was told: "Fatimah bint Ali." The Prophet (peace and blessings be upon him) turned towards Sayyiduna A'idh bin Amr (may Allah be pleased with him), then married that woman to him, and enjoined him (to take good care) of her.
Al-Tabarani recorded it in al-Mu'jam al-Kabir, and it contains unknown (majhul) narrators.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الجنائز / 4055