Answer
The legitime of legitimate children and descendants is one-half of the estate, divided equally among them (Civil Code Article 888); the remaining half is the free portion the testator may dispose of, subject to the legitime of the surviving spouse.
For an illegitimate (nonmarital) child the rule changed with the Family Code: for the estate of a person who died on or after 3 August 1988, every illegitimate child is entitled to a legitime equal to one-half that of a legitimate child (Article 176 of the Family Code). The Civil Code's older two-tier scheme in Articles 287 and 895 governs only estates of persons who died before that date.
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