Who inherits when collateral relatives are at different degrees of proximity to the deceased?
Chapter on Distant Kindred (Dhawu al-Arham)
Al-Mughni
Book of Inheritance Shares (Farā'id)
Primary text
When some collateral relatives are closer to the deceased than others, the inheritance belongs exclusively to the nearest relative. For example, between a maternal aunt (khala) and the mother of the paternal grandfather (umm abi umm), the inheritance goes to the maternal aunt because she connects through the mother (the closest degree), which is the opinion of the majority of those who calculate inheritance based on proximity. The ruling affirms that inheritance is from the deceased, not from the intermediary cause (the ancestor).
Supporting text
A dissenting view, attributed to al-Nakha'i, Shuraik, and Yahya ibn Adam concerning maternal relatives specifically, is that the mother's share is effectively nullified (amātatu al-umm) and passed to her heirs. Under this view, the maternal aunt receives half of the mother's share (as a sister), the mother of the paternal grandfather receives one-sixth (as a grandmother), and the remainder goes to the paternal uncle's son (as a nephew).