When a person passes away in the Philippines, their estate is distributed according to the Civil Code of the Philippines, specifically under the rules of Succession. Understanding the hierarchy of heirs is crucial, as the law prioritizes certain family members over others, often leading to common misconceptions regarding the rights of siblings versus children.

1. The Concept of Compulsory Heirs

In Philippine law, the estate is divided into two main parts: the Legitime and the Free Portion. The legitime is that part of the testator's property which he cannot dispose of because the law has reserved it for certain heirs, called Compulsory Heirs.

The primary compulsory heirs are:

Legitimate children and descendants.
The surviving spouse.
Illegitimate children.

The Rule of Preference of Lines

The presence of "descendants" (children/grandchildren) generally excludes "collaterals" (siblings). This is a fundamental principle: Succession flows downward before it flows sideways.

2. Inheritance Rights of Children

Children are considered primary compulsory heirs. Their rights vary slightly depending on their legal status:

Legitimate Children: They are entitled to one-half () of the estate, to be divided equally among them.
Illegitimate Children: Under the Family Code and Civil Code, illegitimate children are entitled to a legitime that is equal to one-half () of the share of a legitimate child.
The Surviving Spouse: The spouse inherits a share equal to that of one legitimate child.

Example Scenario

If a deceased person leaves behind two legitimate children and an estate worth PHP 1,000,000:

Child A: PHP 250,000 (Legitime)
Child B: PHP 250,000 (Legitime)
The remaining PHP 500,000 is the Free Portion, which can be given to anyone via a Will. If there is no Will (Intestate), the children usually split the entire amount equally.

3. Inheritance Rights of Siblings

Siblings are not compulsory heirs. They are "Voluntary Heirs" (if named in a Will) or "Legal/Intestate Heirs" (in the absence of a Will and certain other relatives).

When do Siblings inherit?

Siblings only inherit under Intestate Succession (where no Will exists) and only if the following conditions are met:

The deceased left no descendants (children/grandchildren).
The deceased left no ascendants (parents/grandparents).
The deceased left no Will disposing of the property to others.

Full-blood vs. Half-blood Siblings

If siblings are eligible to inherit, the law distinguishes between them:

Full-blood siblings receive a share double that of half-blood siblings.

4. Siblings vs. Children: The Exclusion Rule

If a person dies leaving both children and siblings, the children inherit everything to the exclusion of the siblings. The siblings cannot claim a "legal share" or legitime if the deceased had children. The only way a sibling can inherit alongside a child is if the deceased explicitly named the sibling in a Last Will and Testament, and even then, the gift can only be taken from the Free Portion of the estate.

5. Summary Table of Succession

Heir	Status	Right to Legitime?	Priority
Children	Primary Compulsory	Yes	1st Priority; excludes parents and siblings.
Parents	Secondary Compulsory	Yes	Only inherits if there are no children.
Spouse	Primary Compulsory	Yes	Inherits alongside children or parents.
Siblings	Collateral/Legal	No	Only inherits if no children or parents exist.

6. Important Considerations

The Iron Curtain Rule (Article 992): An illegitimate child has no right to inherit ab intestato (without a will) from the legitimate children and relatives of his father or mother; nor shall such children or relatives inherit in the same manner from the illegitimate child.
Right of Representation: If a child predeceases the parent, the grandchildren can represent that child. Similarly, if a sibling is eligible to inherit but has died, their own children (nephews/nieces of the deceased) may inherit by right of representation.

Would you like me to draft a sample computation of shares based on a specific family scenario or estate value?