Answer
When a person dies without a valid will, the estate passes by intestate succession in this order (Civil Code Article 960 and following): legitimate children and descendants; legitimate parents and ascendants; illegitimate children; the surviving spouse; brothers and sisters, nephews and nieces; other collateral relatives up to the fifth degree; and finally the State. The surviving spouse and illegitimate children are concurring heirs — they inherit together with the descendants or ascendants, not merely after them.
One long-standing limit — the “iron curtain” of Article 992, which barred an illegitimate child from inheriting from the legitimate relatives of the parent — was reinterpreted by the Supreme Court in Aquino v. Aquino (G.R. Nos. 208912 and 209018, 7 December 2021): a nonmarital child may inherit from a legitimate grandparent by right of representation once filiation is proven, and the bar is now confined to the collateral line.
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