Mustawrid narrates: A man came to Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) and said: "My paternal uncle married me to his slave-girl, and now he wants to take my children away (by making them slaves)." Sayyiduna Abdullah (may Allah be pleased with him) said: "He has no such right."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 9172