Short answer. Yes, serious illness of the husband is one of the grounds under Article 166 of the Family Code for impugning a child's legitimacy — but only if the illness absolutely prevented sexual intercourse during the first 120 days of the 300-day period before birth. Grave illness alone, without that absolute prevention, is not enough.
What the law says
serious illness of the husband, which absolutely prevented sexual intercourse
Family Code, Article 166 — Grounds to Impugn Legitimacy. Read the full provision →
The ground is narrow: absolute prevention, not merely difficulty
Article 166 of the Family Code allows legitimacy to be impugned on grounds of the husband's serious illness, but it sets a demanding standard. The illness must have absolutely prevented sexual intercourse. A husband who was seriously ill but still physically capable of sexual intercourse cannot rely on this ground. The word "absolutely" is not accidental — the legislature understood that illness ranges from bedridden incapacity to manageable conditions, and it confined this ground to the former extreme.
The critical time window
Even where the illness was absolutely incapacitating, it must have existed within the first 120 days of the 300 days which immediately preceded the birth of the child. That window corresponds to the possible period of conception. If the husband was gravely ill during a different period — say, only in the final weeks of the pregnancy — the ground is not established, because the illness did not cover the time when conception could have occurred. Matching the timing of the illness to the conception window is essential to any action.
What evidence is likely needed
Establishing that an illness absolutely prevented sexual intercourse is not something the court will accept on the husband's word alone. Medical records, hospital confinement records, physician testimony, and other objective evidence documenting the nature and severity of the illness during the relevant period are the type of proof typically required. The more severe and documented the incapacitation, the stronger the case. Conditions that are serious but leave the husband ambulatory and otherwise functional will be difficult to characterize as absolutely preventing intercourse.
Legitimacy is presumed — the burden is on the person impugning
Under Article 164 of the Family Code, children conceived or born during marriage are legitimate. That presumption is strong by design, to protect children and the stability of family relations. The person seeking to impugn the child's legitimacy carries the burden of proving the ground and meeting the applicable deadline for filing an action. The grounds in Article 166 are exhaustive — legitimacy may be impugned only on those grounds, and the serious illness ground is just one of them.
Cases citing this provision
These Supreme Court decisions cite the provision above. We list them so you can read them yourself; the summaries of what each decided are not ours to give.
- Bernie Santiago vs. Rommel C. Jornacion and The City Civil Registrar of Marikina City, G.R. No. 230049, October 6, 2021 — read the decision on LawPhil →
- Lowella Yap vs. Almeda Yap, Hearty Yap-Dybongco and Diosdado Yap, Jr, G.R. No. 222259, October 17, 2022 — read the decision on LawPhil →
- Richelle Busque Ordoña vs. The Local Civil Registrar of Pasig City and Allan D, G.R. No. 215370, November 9, 2021 — read the decision on LawPhil →
- Eugenio San Juan Geronimo vs Karen Santos, G.R. No. 197099, September 28, 2015 — read the decision on LawPhil →