Entangled successions: when the heir dies before division

The four situations

First situation: it is known that one died before the other: the survivor keeps his right over the deceased's wealth, and his own heirs gather it afterwards; inheritance requires the heir's life at the moment of the deceased's death. Second situation: both died together in one circumstance (drowning, wall collapse, fire, battle): agreement of the scholars: neither transmits to the other; each one's estate goes directly to his own living heirs, for one was no longer alive at the other's death (agreement reported by al-Mawardi and others). Third situation: the order of death is unknown: Hanafis and Malikis: no inheritance between them, each one's wealth goes to his own heirs. Fourth situation: the prior death of one is certain but the identity of the predeceased is unknown: the schools resort to simultaneous attribution: each is treated as having died first, each branch benefiting its heirs; the faraid books give the worked examples, like the two drowned men with their spouses, mother and uncle, set upon thirteen, six then seventy-two shares (Al-Mughni, Ibn Abidin).

The captive and the missing

The same reasoning applies when two relatives disappear together: the jurists rank the presumptions of survival. When the heirs specify the death of one while still doubting the other: the one whose death remains doubtful inherits from the identified dead, the origin being the maintenance of life.

Practical note

After a disaster, the simple rule: date each death if possible; failing that, each passes through his own heirs; the complexity of combined calculations refers to the tables of the jurists specialized in the faraid.