That she was married to Sad bin Khaula
who was from the tribe of Bani 'Amr bin Luai, and was one of those who
fought the Badr battle. He died while she wa pregnant during
Hajjat-ul-Wada.' Soon after his death, she gave birth to a child. When
she completed the term of deliver (i.e. became clean), she prepared
herself for suitors. Abu As-Sanabil bin Bu'kak, a man from the tribe
of Bani Abd-ud-Dal called on her and said to her, "What! I see you
dressed up for the people to ask you in marriage. Do you want to marry
By Allah, you are not allowed to marry unless four months and ten days
have elapsed (after your husband's death)." Subai'a in her narration
said, "When he (i.e. Abu As-Sanabil) said this to me. I put on my
dress in the evening and went to Allah's Messenger (ﷺ) and asked him about
this problem. He gave the verdict that I was free to marry as I had
already given birth to my child and ordered me to marry if I wished."
Sahih al-Bukhari Book 64, Hadith 42