Yahya related to me from Malik from Hisham ibn Urwa that he hearda man ask Urwa ibn az-Zubayr about a man who said to his wife, "Anywoman I marry along with you as long as you live will be like mymother's back to me." Urwa ibn az-Zubayr said, "The freeing of slavesis enough to release him from that."
USC-MSA web (English) reference: Book 29, Hadith 23
Arabic reference: Book 29, Hadith 1180