You would have received a greater reward had you given her to your maternal uncles
Authentic hadithعن أم المؤمنين ميمونة بنت الحارث رضي الله عنها : أنها أعتقت وَليدَةً ولم تستأذن النبي صلى الله عليه وسلم فلما كان يَومُها الذي يَدورُ عليها فيه، قالت: أشَعَرْتَ يا رسول الله، أني أعتقت وليدتي؟ قال: «أو فعلت؟» قالت: نعم. قال: «أما إنك لو أعطيتها أخوالك كان أعظم لأجرك».
The Mother of the Believers Maymūnah bint al-Hārith (may Allah be pleased with her) reported that she had set free a slave-girl of hers without first seeking the permission of the Prophet (may Allah's peace and blessings be upon him). On the day when it was her turn to have the Prophet (may Allah's peace and blessings be upon him) stay with her overnight, she said to him: "O Messenger of Allah, do you know that I set free my slave-girl?" He said: "Did you?" She replied: ‘Yes.’ He then said: "you would have received a greater reward had you given her to your maternal uncles."
Explanation
In this Hadīth, Maymūnah bint al-Hārith (may Allah be pleased with her) freed a slave-girl of hers, because of her knowledge of the virtue of freeing slaves for the sake of Allah. She did this without informing or consulting the Prophet (may Allah’s peace and blessings be upon him). When it was the day when the Prophet would stay at her house overnight, she told him what she had done. He did not blame her for freeing the slave without first consulting him, but he only informed her that had she given that girl to her maternal uncles, she would have received a greater reward. In other words, he approved of and praised what she did, but told her that had she given it to her uncles from Banu Hilāl, it would have been better and she would have earned a greater reward due to the virtue of giving charity to one's relatives and maintaining good ties with them.
Source · Narrated by Bukhari & Muslim
From the Hadith Encyclopedia (hadeethenc.com).