Narrated Kurib:

the freed slave of Ibn 'Abbas, that Maimuna bint Al-Harith told him that she manumitted a slave-girl without taking the permission of the Prophet. On the day when it was her turn to be with the Prophet, she said, "Do you know, O Allah's Apostle, that I have manumitted my slave-girl?" He said, "Have you really?" She replied in the affirmative. He said, "You would have got more reward if you had given her (i.e. the slave-girl) to one of your maternal uncles."

حَدَّثَنَا يَحْيَى بْنُ بُكَيْرٍ، عَنِ اللَّيْثِ، عَنْ يَزِيدَ، عَنْ بُكَيْرٍ، عَنْ كُرَيْبٍ، مَوْلَى ابْنِ عَبَّاسٍ أَنَّ مَيْمُونَةَ بِنْتَ الْحَارِثِ ـ رضى الله عنها ـ أَخْبَرَتْهُ أَنَّهَا، أَعْتَقَتْ وَلِيدَةً وَلَمْ تَسْتَأْذِنِ النَّبِيَّ ﷺ، فَلَمَّا كَانَ يَوْمُهَا الَّذِي يَدُورُ عَلَيْهَا فِيهِ قَالَتْ أَشَعَرْتَ يَا رَسُولَ اللَّهِ أَنِّي أَعْتَقْتُ وَلِيدَتِي قَالَ " أَوَفَعَلْتِ ". قَالَتْ نَعَمْ. قَالَ " أَمَا إِنَّكِ لَوْ أَعْطَيْتِيهَا أَخْوَالَكِ كَانَ أَعْظَمَ لأَجْرِكِ ".
وَقَالَ بَكْرُ بْنُ مُضَرَ عَنْ عَمْرٍو عَنْ بُكَيْرٍ عَنْ كُرَيْبٍ إِنَّ مَيْمُونَةَ أَعْتَقَتْ.