Narrated from Umm al-Mu’minin Aisha Siddiqa (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) was sitting with her when Aisha Siddiqa (may Allah be pleased with her) heard a voice that someone was seeking permission to enter at the door of Umm al-Mu’minin Hafsa (may Allah be pleased with her). So Aisha (may Allah be pleased with her) said,“O Messenger of Allah! Someone is asking permission to enter your house.”The Prophet (peace and blessings be upon him) said,“I think it is so-and-so, who is Hafsa’s (may Allah be pleased with her) foster uncle.”Umm al-Mu’minin Aisha Siddiqa (may Allah be pleased with her) asked,“O Messenger of Allah! If so-and-so (my own foster uncle) were alive, could he come into my house?”The Prophet (peace and blessings be upon him) said,“Yes, the prohibition (of marriage) due to fosterage is the same as that due to birth.”

Umm al-Mu’minin Aisha (may Allah be pleased with her) says: My foster uncle came and asked permission to enter, but I refused to give him permission until I could consult the Prophet (peace and blessings of Allah be upon him) about it. When the Messenger of Allah (peace and blessings of Allah be upon him) came, I told him that my foster uncle had asked to come to me, but I refused. The Prophet (peace and blessings of Allah be upon him) said: Your uncle may come to you. I said: The woman nursed me, not the man (i.e., how can the rights of a man be established when the woman gave the milk?). The Prophet (peace and blessings of Allah be upon him) said: He may come to you.

Amir al-Mu’minin Sayyiduna Ali (may Allah be pleased with him) says: I said,“O Messenger of Allah! What is it that you eagerly marry within the (family of) Quraysh but leave us aside? (That is, we have proposals available but you do not accept them.)”So the Messenger of Allah (peace and blessings be upon him) said,“Do you have any proposal?”I said,“Yes, (the chief of martyrs) Hamzah’s (may Allah be pleased with him) daughter (who was the cousin of the Prophet Muhammad, peace be upon him, and Sayyiduna Ali, may Allah be pleased with him).”The Prophet Muhammad (peace and blessings be upon him) said,“She is not lawful for me, because she is the daughter of my foster brother.”(The reason was that the Prophet Muhammad, peace be upon him, and Sayyiduna Hamzah, may Allah be pleased with him, both drank the milk of the same woman.)

Umm al-Mu’minin Umm Habibah bint Abi Sufyan (may Allah be pleased with her) says: The Messenger of Allah (peace and blessings be upon him) came to me, so I said,“What is your opinion about my sister, the daughter of Abu Sufyan?”The Prophet (peace and blessings be upon him) said,“So what should I do?”I said,“You should marry her.”(At that time, Umm al-Mu’minin Umm Habibah (may Allah be pleased with her) did not know that it is forbidden to have two sisters together in marriage.) Then the Prophet (peace and blessings be upon him) said,“Would you like that?”I said,“I am not the only one in your marriage, and I would like that the one who shares goodness with me should be my sister.”The Prophet (peace and blessings be upon him) said,“She is not lawful for me.”I said,“I have heard that you have sent a marriage proposal to Durrah bint Abi.”The Prophet (peace and blessings be upon him) said,“The daughter of Umm Salamah?”I said,“Yes.”The Prophet (peace and blessings be upon him) said,“Even if she had not been raised in my lap, she would still not be lawful for me, because she is my niece through breastfeeding. Thuwaibah nursed both me and her father (Sayyiduna Abu Salamah, may Allah be pleased with him). So do not send me proposals for your daughters and sisters.”

Lady Umm Fadl (may Allah be pleased with her) says that a man from a village came to the Messenger of Allah (peace and blessings be upon him) while he was in my house. He said, "O Prophet of Allah! I had a wife and I married another woman. My first wife claims that she suckled the second woman once or twice." The Messenger of Allah (peace and blessings be upon him) said, "Prohibition is not established by suckling once or twice."

‘It is narrated from Umm al-Mu’minin Aisha Siddiqa (may Allah be pleased with her)’ she said: At first, the command was revealed in the Qur’an that prohibition is established by ten sucklings. Then this was abrogated and it was revealed that prohibition is caused by five sucklings. And when the Messenger of Allah (peace and blessings of Allah be upon him) passed away, this was being recited in the Qur’an.

It is narrated from Umm al-Mu’minin Aisha Siddiqa (may Allah be pleased with her) that Salim, the freed slave of Abu Hudhaifah (may Allah be pleased with them), used to live with their family in their house. Suhail’s daughter (i.e., the wife of Abu Hudhaifah) came to the Messenger of Allah (peace and blessings be upon him) and said:“Salim has reached puberty and understands the matters of men, and he comes into our house. I think Abu Hudhaifah feels dislike about this matter in his heart.”The Noble Prophet (peace and blessings be upon him) said:“Breastfeed Salim so that he becomes unlawful (mahram) for you, and the dislike that Abu Hudhaifah feels in his heart will go away.”Then she came again and said:“I have breastfed him, and the dislike that Abu Hudhaifah (may Allah be pleased with him) felt has gone away.”

Lady Zainab bint Umm Salamah (may Allah be pleased with them) used to say that all the wives of the Prophet (peace and blessings of Allah be upon him) denied that anyone should come into their house and drink milk in this manner (i.e., that an adult should be given milk as mentioned in the previous hadith). And Umm al-Mu'mineen Aisha Siddiqah (may Allah be pleased with her) used to say that we only know that this was a special concession from the Prophet (peace and blessings of Allah be upon him) for Salim, and the Prophet (peace and blessings of Allah be upon him) never brought anyone before us and had them drink milk in this way, nor do we consider it permissible.

Umm al-Mu’minin Aisha Siddiqa (may Allah be pleased with her) says that the Messenger of Allah (peace and blessings be upon him) came to me while a man was sitting with me. This was very displeasing to the Prophet (peace and blessings be upon him), and I saw anger on his face. So I said,“O Messenger of Allah! This is my milk-brother.”The Prophet (peace and blessings be upon him) said,“Be careful in verifying milk-brothers, for suckling is only valid when it is during hunger (i.e., during the period of suckling, meaning within two years).”(Or it means that suckling is established only when the child drinks enough milk to satisfy his hunger. Suckling is not established by just a sip or two. And Allah knows best.)