690 – From ʿAlī ibn Abī Ṭālib (rA) who said: “The Messenger of Allah ﷺ ordered me to sell two slave boys who were brothers. I sold them and thereby separated them, then I mentioned that to the Prophet ﷺ. He said, ‘Go after them, take them back, and do not sell them except together.’”

Aḥmad recorded it; its transmitters are trustworthy, and it was declared authentic by Ibn Khuzaymah, Ibn al-Jārūd, Ibn Ḥibbān, al-Ḥākim, al-Ṭabarānī, and Ibn al-Qaṭṭān. (1)

Hadith grading:
This report is good (ḥasan) on account of corroborating chains.
The author states: It was transmitted by Aḥmad with reliable narrators, and authenticated by Ibn Khuzaymah, Ibn al-Jārūd, Ibn Abī Ḥātim, al-Ḥākim, al-Ṭabarānī, and Ibn al-Qaṭṭān.
In al-Talkhīṣ he writes: “The ḥadith of ʿAlī—he separated a female slave from her child, so the Prophet ﷺ forbade him and revoked the sale—was recorded by Abū Dāwūd, though a break was noted between Maymūn ibn Abī Shaybīb and ʿAlī ibn Abī Ṭālib; al-Ḥākim also narrated it and judged its chain sound.”
Al-Bayhaqī preferred it because of its supporting narrations, and al-Haythamī said: “The transmitters in Aḥmad’s chain are the men of the Ṣaḥīḥ.”

Points derived from the two ḥadiths:
1 – Hadith 689 shows that it is forbidden to separate a mother from her child among slaves, whether through sale or by any other transfer of ownership.
2 – The general wording of the ḥadith indicates that separation is prohibited even after the child reaches puberty. In Sharḥ al-Iqnāʿ it states: “It is unlawful and invalid to separate blood relatives through sale, division, gift, or anything similar—even after puberty—because of the general purport of Abū Ayyūb’s ḥadith.” Thus the jurists extended the ruling to all close kin.