It is narrated from Sayyiduna al-Miswar bin Makhramah (may Allah be pleased with him) that the husband of Subay'ah al-Aslamiyyah (may Allah be pleased with her) died while she was pregnant, and only a few nights later she gave birth. When she had become pure, she received a proposal of marriage, and having given birth she asked the Messenger of Allah (peace and blessings be upon him) for permission to marry. He (peace and blessings be upon him) gave her permission, and she married.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17141