Inheritance Rights of an Unadopted Child Named in a Will (Philippines)

Scope. This is a practitioner-style explainer on how Philippine succession law treats a person whom the testator calls a “child” in the will without a completed adoption. It covers (1) when that person is merely a legatee/devisee (a beneficiary of a specific gift), (2) when he or she is also a biological child (illegitimate or legitimate) and how that changes rights, and (3) drafting and litigation tips. General information only, not legal advice.

1) First fork: Who is the “unadopted child”?

Not biologically related (e.g., stepchild, foster child, ward) and never adopted.
- Status: a stranger in intestacy.
- Rights: can inherit only because the will says so, and only from the free portion after setting aside the legitimes of compulsory heirs.
- If the will is denied probate or is silent about them: they get nothing under intestacy.
Biological child (illegitimate), not adopted.
- Status: an illegitimate child, a compulsory heir with a legitime (forced share) even without a will—if filiation is established.
- Effect of being named in the will: may increase what they get (within the free portion) and/or confirm filiation if the will contains an express acknowledgment.
Biological child (legitimate).
- This article assumes no adoption has occurred. If the child is legitimate by law (e.g., born in wedlock, or legitimated), adoption is irrelevant; that child is already a compulsory heir.

Key: Adoption (now governed by the Domestic Administrative Adoption and Alternative Child Care framework) creates legal filiation and legitimacy; without it, a non-biological “child” remains a stranger in succession unless and until the will grants a testamentary gift.

2) Two titles in wills: heir vs. legatee/devisee

Instituted heir (universal title): succeeds to the estate or a fractional share of it.
Legatee/devisee (singular title): receives a specific amount (legacy) or specific thing/realty (devise).

An unadopted non-biological “child” can be either, but whatever the label, the gift cannot impair the legitimes of compulsory heirs. If it does, a court will reduce it as inofficious.

3) Compulsory heirs & the free portion (quick map)

Compulsory heirs include: legitimate children/descendants; in their absence, legitimate parents/ascendants; the surviving spouse; and illegitimate children. The portion they cannot be deprived of (their legitime) is reserved by law. What remains is the free portion, which the testator can give to anyone (including a non-biological, unadopted “child”).

Very high-level illustrations for a net hereditary estate (after debts/expenses):

Spouse + 2 legitimate children (no illegitimate children):
- Legitimate children’s collective legitime = ½ (split equally).
- Spouse’s legitime = equal to one legitimate child’s legitime (here, ¼).
- Free portion = ¼.
- A non-biological “child” named in the will can be given up to ¼ in total; any excess is reduced.
Spouse + 1 legitimate child + 1 illegitimate child:
- Legitimate child’s legitime = ½.
- Illegitimate child’s legitime = ½ of a legitimate child’s legitime = ¼.
- Spouse’s legitime (with legitimate children) = ¼.
- Free portion = 0.
- A non-biological “child” can still be named, but only subject to reduction to zero if needed to preserve those legitimes.

The free portion is computed after fictitious collation of certain lifetime donations. Gifts (even years earlier) can be pulled back on paper to test if the legitimes were impaired; inofficious donations are reduced.

4) If the unadopted child is not biologically related

What they can receive

Whatever the will gives them from the free portion: a fixed sum, a specific asset, or even a fractional share (as instituted heir).
They may also be substitutes or residuary beneficiaries for the free portion.

What can defeat or reduce their gift

Insufficient free portion after computing legitimes → reduction (proportional if multiple free-portion beneficiaries).
Preterition of a compulsory heir in the direct line (e.g., a legitimate child totally omitted): this annuls the institution of heirs in the will, but legacies/devices survive insofar as not inofficious. Practical tip: give a specific legacy to the unadopted child rather than making them the sole “heir,” to lessen preterition risk.
Invalid will (formal defects; lack of testamentary capacity) → if probate fails, there’s no testamentary entitlement to a non-biological child.

What they cannot claim

No intestate rights;
No legitime;
No right to collate or to share in reductions affecting only compulsory heirs;
No representation in testate succession (representation is an intestacy concept); their legacy lapses if they predecease the testator unless there’s substitution or accretion conditions that save it.

5) If the unadopted child is the biological child (illegitimate)

Filiation is the gate

Establish filiation by the modes allowed by law (e.g., civil registry, public/handwritten acknowledgment, or other admissible evidence).
A will can contain an express acknowledgment of filiation. Even if the testamentary dispositions fail, the acknowledgment itself may still serve as written proof of filiation if it meets statutory requisites.

Once filiation is established

The illegitimate child becomes a compulsory heir entitled to a legitime (traditionally ½ of a legitimate child’s legitime), to be respected before free-portion gifts are satisfied.
If the will also leaves a legacy to the child, that legacy is charged to the free portion and is on top of the legitime (subject to reduction if total exceeds what’s disposable).

Timing & procedure note. Actions to establish filiation and to claim legitime involve tight rules on evidence and, in some situations, time limits. Counsel should move promptly in the estate or in a separate case when needed.

6) Drafting to benefit an unadopted (non-biological) child

Identify them precisely. Full name, date of birth, and relationship description (e.g., “my step-daughter”).
Use specific legacies (“₱X” or “Unit 3C, ABC Condo”) so that, if there’s preterition, the gift is more likely to survive up to the free portion.
Add substitution (“If A predeceases me, then to B”) to prevent lapse.
Stage gifts (cash + life usufruct; or trust terms) so reductions, if any, don’t unintentionally wipe out all benefits.
Coordinate lifetime planning: inter vivos donations (mind inofficiousness), insurance designations, and trusts. (Some assets pass outside probate, but estate and donor’s-tax/inofficiousness rules still matter—get tax and succession advice.)
Avoid accidental preterition: always mention known compulsory heirs and give them at least their legitimes, or expressly state a universal residuary clause that respects them.

7) Litigation posture for the named unadopted child

During probate:
- Appear or intervene to (a) support allowance of the will and (b) defend the legacy against reduction arguments.
- Track the legitime math (net estate, collation, debts) to contest overbroad reductions.
- If biologically related, consider filing to establish filiation and claim legitime early.
If the gift is reduced:
- Reductions are typically proportional among those drawing from the free portion; ensure others are reduced fairly.
- If a specific thing was given and the free portion is insufficient, the court may order money equivalent or allow mixed satisfaction (e.g., cash + asset share), depending on feasibility.

8) Common pitfalls

Naming a stepchild as sole “heir” while omitting a legitimate child → preterition blows up the institution; only legacies (if any) may survive.
Over-gifting from the free portion → guaranteed reduction fight later.
Assuming foster/step status creates intestate rights → it does not.
Failing to lock in filiation evidence for a biological (illegitimate) child → risks losing a legitime that would otherwise be automatic.

9) Worked mini-examples (₱12,000,000 net estate)

Spouse + 2 legitimate children + stepchild (named).
- Children’s legitime (½) = ₱6,000,000 (₱3,000,000 each).
- Spouse’s legitime = ₱3,000,000 (equal to one child).
- Free portion = ₱3,000,000 → maximum the stepchild (a stranger) can take in total.
Spouse + 1 legitimate child + 1 illegitimate child + stepchild (named).
- Legitimate child’s legitime = ₱6,000,000.
- Illegitimate child’s legitime = ₱3,000,000 (½ of a legitimate child’s legitime).
- Spouse’s legitime = ₱3,000,000.
- Free portion = ₱0 → any gift to the stepchild is fully reducible to zero if needed to satisfy those legitimes.

(Arithmetic checked: 6,000,000 + 3,000,000 + 3,000,000 = 12,000,000; no free portion remains.)

10) Practical checklists

For testators who want to provide for an unadopted (non-biological) child

Map your compulsory heirs; rough out legitime/free-portion math.
Use specific legacies with substitution; avoid making them your sole heir if you have compulsory heirs.
Consider adoption (if appropriate) or, for a biological child, include express acknowledgment of filiation.
Coordinate with lifetime gifts/insurance/trusts mindful of tax and inofficiousness limits.
Keep will formalities tight; store the original; tell your executor where it is.

For an unadopted child named in a will (after death)

Enter the probate; get counsel.
Demand a proper inventory and collation analysis; check the free-portion computation.
If biological, assert filiation and legitime with admissible proof.
Prepare for reduction scenarios; negotiate equivalents if a specific asset gift cannot be delivered in full.

11) Bottom line

A non-biological, unadopted child has no intestate share and no legitime, but can take whatever the free portion permits under a valid will.
A biological (illegitimate) child—even if not adopted—can be a compulsory heir once filiation is established, and any testamentary gift comes on top of that legitime (subject to reduction).
Smart drafting (or early litigation strategy) often determines whether the named unadopted child actually receives what the testator intended.