The Law Code of Bṛhaspati 1.26.136

1.26.136

putrābhāve tu patnī syāt patnyabhāve tu sodaraḥ /
tadabhāve tu dāyādaḥ paścād dauhitrakaṃ dhanam //

But on his death the mother shall take a son's share. The mothers shall share equally with the sons, the maidens shall take fourth-part shares.
65, 66. To a father the funeral ball (Pinda) and water oblation shall be offered by his son; in default of a son, the widow (succeeds); in her default, a uterine brother; in default of him, the co-heirs (dâyâdâh); afterwards, the property goes to the daughter's son.