Who should light the funeral pyre (mukhāgni)?

usually the eldest son, but any close family member — a daughter, wife, younger son or grandson — may do it.

The person who gives mukhāgni (the first fire) is called the kartā. Custom usually names the eldest son for a father and the youngest son for a mother in some regions, but this is a family convention, not a rule that blocks everyone else. The Dharmaśāstra digests list a long order of who may act when a son is absent: wife, daughter, grandson, brother, nephew, and even a disciple or friend.

Today many daughters and wives light the pyre of their parents and husbands, and priests across India accept this. What matters is love, sincerity and that someone close carries the rites through.

Practically, decide on the kartā early, because the same person usually performs the daily rites until the 10th–13th day. If the son is abroad and cannot arrive in time, another family member can begin, and he can join the later rites.

Source: Garuḍa Purāṇa; Dharmasindhu · Daughters and wives may light the pyre

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