Hadith 5911
عَنْ أَبِي أَيُّوبَ الْأَنْصَارِيِّ رَضِيَ اللَّهُ عَنْهُ عَنْ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ أَنَّهُ قَالَ مَنْ فَرَّقَ بَيْنَ الْوَلَدِ وَوَالِدِهِ فِي الْبَيْعِ فَرَّقَ اللَّهُ عَزَّ وَجَلَّ بَيْنَهُ وَبَيْنَ أَحِبَّتِهِ يَوْمَ الْقِيَامَةِ
Narrated by Sayyiduna Abu Ayyub Ansari (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Whoever, while trading (slaves), separates a child from his parents, Allah Almighty will separate him from his loved ones on the Day of Resurrection.
Hadith 5912
عَنْ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ قَالَ أَمَرَنِي رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ أَنْ أَبِيعَ غُلَامَيْنِ أَخَوَيْنِ فَبِعْتُهُمَا فَفَرَّقْتُ بَيْنَهُمَا فَذَكَرْتُ ذَلِكَ لِلنَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ فَقَالَ أَدْرِكْهُمَا فَأَرْجِعْهُمَا وَلَا تَبِعْهُمَا إِلَّا جَمِيعًا
It is narrated from Sayyiduna Ali bin Abi Talib (may Allah be pleased with him), he says: The Messenger of Allah (peace and blessings be upon him) ordered me to sell two slaves; they were brothers to each other. I sold them, but I separated them from each other, and then I informed the Messenger of Allah (peace and blessings be upon him) of this. He (peace and blessings be upon him) said: Find both of them and return them, and do not sell them except together.