822 – Ibn Buraydah narrated from his father (may Allah be pleased with him) that “the Prophet ﷺ assigned to the grandmother one-sixth, provided that no mother stands between her and the deceased.” Abū Dāwūd and al-Nasāʾī recorded it; Ibn Khuzaymah and Ibn al-Jārūd declared it sound, and Ibn ʿAdī considered it strong.⦗1⦘

Hadith grading
This report is ḥasan (good). Abū Dāwūd transmitted it through the chain of ʿUbayd Allāh Abū al-Munīb al-ʿAtakī. Al-Ḥāfiẓ said of him, “reliable but prone to error,” yet Ibn al-Sakan authenticated the hadith.

Points derived from the two hadiths

1. Hadith no. 821 shows that a grandfather with no father between him and the deceased receives one-sixth as a fixed share, with the remainder by agnation. Thus, when a man dies leaving two daughters and his grandfather, the daughters take two-thirds as a prescribed share, the grandfather one-sixth as a prescribed share, and he also receives the remaining one-sixth through agnation.
2. The second hadith clarifies that the grandmother is entitled to one-sixth, on condition that there is no living mother who would bar her.
3. An inheritance rule states that heirs who share the same lineage tier and degree share equally in the estate. Consequently, if several grandmothers who are all in the same degree qualify as heirs, they divide the one-sixth among themselves.
4. Another rule of succession is that a nearer heir excludes a more remote one. Therefore, the closer grandmother bars the more distant grandmother, regardless of her line of descent, according to the stronger opinion.