An illegitimate child is born to parents who are not married to each other at the time of the child's birth. Even if the parents later married, the child would still be considered illegitimate.

• Born BEFORE August 3, 1988
  • If acknowledged by both parents.
  • If acknowledged by one parent.
  • Child under the surname of the mother and acknowledge by the father through authentic writing.
• Born AFTER August 3, 1988
  • Birth Certificate already registered and child is under the surname of the mother and a Private Handwritten Instrument by the father is present.
  • Birth Certificate already registered and child is under the surname of the mother and the father executed an afidavit of acknowledgement.
  • Birth Certificate is not yet registered and the Father acknowledges the child at the back of the birth certificate or in a separate public instrument.