Answer
Compulsory heirs are the persons a testator cannot deprive of their inheritance without a valid cause; the law reserves a portion of the estate — the legitime — for them (Civil Code Article 886). Under Article 887 they are: legitimate children and descendants; in their default, legitimate parents and ascendants; the surviving spouse; and illegitimate (nonmarital) children.
The surviving spouse and illegitimate children concur with — they do not exclude — the legitimate children or ascendants. Legitimate parents and ascendants inherit as compulsory heirs only when the decedent leaves no legitimate children or descendants.
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