Musannaf Ibn Abi Shaybah

Hazrat Nafi’ narrates that when Hazrat Aisha (may Allah be pleased with her) intended that a child, after growing up, would be able to visit her, she would instruct one of her female relatives to breastfeed him. (so that Hazrat Aisha (may Allah be pleased with her) would become his foster aunt (maternal or paternal).) In this regard, she instructed (her sister) Hazrat Umm Kulthum to give Hazrat Salim (when he was a child) ten sucklings, (so that Salim would become Hazrat Aisha’s foster nephew). She gave him three sucklings and then became ill, so he did not come to her when he grew up. Similarly, (Hazrat Hafsa bint Umar (may Allah be pleased with her)) instructed Fatima bint Umar to give Asim ibn Sa’d (when he was a child) ten sucklings (so that Asim ibn Sa’d would become her foster nephew). Thus, she did so, and he used to come to her.