Can an adopted child perform a parent’s last rites and śrāddha?

yes — tradition gives the adopted child the same right and duty as a birth child.

One of the reasons Dharmaśāstra discussed adoption at all was to ensure that someone would perform the antyeṣṭi and offer piṇḍa and tarpaṇa to the ancestors. The texts therefore treat the adopted son as taking the place of a natural son in these rites, and today priests across traditions accept adopted daughters and sons equally.

In practice, the adopted child performs the cremation rites, the thirteen-day ceremonies and the annual śrāddha in the adoptive family’s gotra, naming the adoptive parents and their ancestors. If relatives question it, a family priest can usually reassure them that this is long-established.

What the ancestors value is remembrance, love and gratitude. A child who was raised with care and returns that care at the end is fulfilling dharma completely.

Source: Dharmaśāstra on the dattaka son; common priestly practice

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