It is narrated from Miswar bin Makhramah (may Allah be pleased with him) that Sabi’ah Al-Aslamiyyah (may Allah be pleased with her) gave birth to a child a few days after the death of her husband. Then she came to the Messenger of Allah (peace and blessings be upon him) and sought permission to marry, so he (peace and blessings be upon him) granted her permission.
Hadith Referenceمسند الإمام الشافعي / كتاب العدد والسكنى والنفقات / 1303
Hadith Takhrijاخرجه البخاری، الطلاق، باب اولات الاحمال اجلهن أن يضعن حملهن (5320)۔