The phenomenon of "de facto separation"—where spouses live apart without a court decree of legal separation or annulment—is a common reality in the Philippines. While the law (the Family Code) generally envisions a unified household, it provides specific rules for when the family unit fractures informally.

Here is a comprehensive overview of the legal landscape regarding custody and support during de facto separation.

1. Parental Authority and Custody

In a de facto separation, the primary concern is the welfare of the children. Philippine law distinguishes between "parental authority" (the right to provide for and make decisions for the child) and "actual custody" (physical possession).

The Rule of Joint Parental Authority

Even if parents live apart, Article 211 of the Family Code stipulates that joint parental authority continues. Neither parent is automatically divested of their rights just because they moved out.

The "Tender Age" Rule

Under Article 213 of the Family Code, if the parents are separated, the court (or the law) must consider the child's best interest. However, a strict statutory rule applies:

Children under 7 years old: They cannot be separated from the mother unless the court finds compelling reasons (e.g., drug addiction, maltreatment, or insanity). Adultery or "immorality" is generally not enough to deprive a mother of custody unless it directly harms the child’s welfare.
Children 7 years and older: The court will consider the child's preference, but the final decision rests on who is better suited to provide for the child’s holistic development.

The Best Interest of the Child Doctrine

In all custody disputes arising from de facto separation, the "Best Interest of the Child" is the "Supreme Pointer." This overrides the biological preference of the parents if one is proven unfit.

2. Child Support: An Absolute Obligation

De facto separation does not terminate the obligation to provide support. Under Article 194 of the Family Code, support comprises everything indispensable for sustenance, dwelling, clothing, medical attendance, education, and transportation.

Proportionality: Support is always in proportion to the resources of the giver and the needs of the recipient.
Immediate Right: The right to support does not depend on a court order; it exists from the moment the child is born. However, to legally compel a recalcitrant parent, a petition for support must be filed in court.
No Waiver: You cannot "waive" a child's right to future support. Any agreement between parents saying "I won't ask for support if you give me custody" is legally void.

3. Support Between Spouses

Unlike child support, the right to spousal support during de facto separation is more complex:

Generally, the obligation to support each other continues during the marriage.
However, if a spouse leaves the conjugal home without just cause, the court may exempt the remaining spouse from the obligation to provide support to the one who left.

4. Property Relations and Administration

De facto separation does not automatically dissolve the property regime (e.g., Absolute Community of Property or Conjugal Partnership of Gains).

Management: One spouse cannot simply sell or mortgage common property without the other’s consent, even if they have been separated for decades.
Abandonment: If a spouse abandons the other for at least three months or fails to comply with marital obligations, the "aggrieved" spouse may petition the court for:

Receivership.
Judicial separation of property.
Authority to be the sole administrator of the property.

5. The Role of the Barangay and the Courts

Since de facto separation is informal, disputes often start at the Barangay level for mediation (Katarungang Pambarangay).

Barangay Protection Orders (BPO): If the separation involves domestic violence (RA 9262), the mother can seek a BPO, which may include temporary custody and a "stay-away" order against the father.
Petition for Custody/Habeas Corpus: If one parent "kidnaps" or refuses to return a child to the primary caregiver, a petition for Habeas Corpus involving custody of minors is the fastest legal remedy.

6. Summary of Key Legal Effects

Issue	Legal Status in De Facto Separation
Parental Authority	Remains joint unless a court orders otherwise.
Custody (< 7 years)	Mandatory with the mother (with rare exceptions).
Custody (7+ years)	Determined by the child's best interest and preference.
Child Support	Mandatory and demandable; cannot be waived.
Property	Common property remains joint; requires mutual consent for sale.
Succession	Spouses remain legal heirs of each other until the marriage is annulled.

Next Step

Would you like me to draft a formal Demand Letter for Child Support or a Parenting Plan agreement based on these Philippine legal principles?