وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنْ عَائِشَةَ، أَنَّهَا أَرَادَتْ أَنْ تَشْتَرِيَ، جَارِيَةً تُعْتِقُهَا فَقَالَ أَهْلُهَا نَبِيعُكِهَا عَلَى أَنَّ وَلاَءَهَا لَنَا ‏.‏ فَذَكَرَتْ ذَلِكَ لِرَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَ ‏"‏ لاَ يَمْنَعُكِ ذَلِكَ فَإِنَّمَا الْوَلاَءُ لِمَنْ أَعْتَقَ ‏"‏‏.‏

Ibn Umar reported that 'A'isha decided to buy a slave-girl and then set her free, but her masters said: We are prepared to sell her to you on the condition that her right of inheritance would vest with you. She (Hadrat A'isha) made a mention of that to Allah's Messenger (PBUH) whereupon he said: This should not stand in your way. The right of inheritance vests in one who emancipates. Translation Not Available

Book reference: Sahih Muslim Book 20 Hadith 3584
Web reference: Sahih Muslim Book 9 Hadith 1504 a