من لا يحضره الفقيه, volume 4, page 284

Hadith.5639 - Ibn Udhaynah narrated from Zurarah, Bukayr, Muhammad ibn Muslim, Al-Fuḍayl, and Burayd ibn Muawiyah from one of the two Imams (peace be upon them) who said: "The grandfather, when inheriting alongside the paternal siblings, is considered as one of the brothers."

Translation: Bab Ul Qaim Publications·Thaqalayn link·The Arabic above is the original.

Hadith.5640 - Al-Hasan ibn Mahbub narrated from Ali ibn Riʾab from Zurarah, who said: I asked Abu Abdullah (as) about a man who died and left behind his full brother (from the same father and mother) and his grandfather. Imam (as) said: "The inheritance is divided among them as if they were two brothers or even a hundred. The grandfather is considered as one of them; he receives a share equal to that of one of the brothers."

Translation: Bab Ul Qaim Publications·Thaqalayn link·The Arabic above is the original.

Hadith.5641 - Hammad narrated from Hariz from Al-Fuḍayl or someone else from Abu Abdullah (as) who said: "The grandfather shares the inheritance with the siblings, and his share is equal to the share of one of them, regardless of whether they are many or few."

Translation: Bab Ul Qaim Publications·Thaqalayn link·The Arabic above is the original.

Hadith.5642 - Muhammad ibn Al-Walid narrated from Hammad ibn Uthman from Ismaʿil Al-Juʿfi who said: I heard Abu Jafar Imam Muhammad ibn Ali Al-Baqir (as) say: "The grandfather shares the inheritance with the siblings, even if they were one hundred thousand."

Translation: Bab Ul Qaim Publications·Thaqalayn link·The Arabic above is the original.

Hadith.5643 - Ibn Abi Umayr narrated from Ibn Muskan from Abu Baṣir, who said: I asked Abu Abdullah (as) about a man who died and left behind six brothers and a grandfather. Imam (as) said: "The grandfather is considered as one of them."

Translation: Bab Ul Qaim Publications·Thaqalayn link·The Arabic above is the original.