The Law Code of Devala 6.1: Vīramitrodaya · Nirṇayasindhu · Śrāddhadīpa +3

6.1

anena vidhinā śrāddhaṃ kuryāt saṃvatsare sakṛt | dviś caturvā yathāśraddhaṃ māse māse dine dine

At a death or a birth, for female slaves, / and for wives taken in natural order of castes, / purification is equal to that of the master; when the master dies, it is by uterine kinship.

By this rule he should perform the śrāddha once a year, or twice or four times as his faith allows, or every month, or every day.