Musannaf Ibn Abi Shayba 9:344

Yahya ibn Sa'id narrated to us, from Ibn Jurayj, from Ibn Abi Mulayka, that Mu'adh ibn 'Abd Allah ibn Ma'mar asked 'A'isha and said: "I have a slave girl whom I have had intercourse with, and she has a daughter who has reached puberty, and I have had intercourse with her." She forbade him and said: "No, until you say she is forbidden [to me]." She said: "No one from my family, nor anyone who obeys me, does that." And I asked Ibn 'Umar, and he forbade me from it.