Yahya bin Khlf al-Bahly يحيى بن خلف الباهلي أبو سلمة البصري · The Chapters on Marriage

the Messenger of Allah said: “A man should not propose to a woman to whom his brother has already proposed.”

that the Prophet entered upon her and there was a man with her. He said: “Who is this? She said: “This is my brother.” He said: “Look at whom you allow to enter upon you, because the breastfeeding (that makes a person Mahram) is that which satisfies hunger.”