Some children carry a little bit more inside of them than just lineage.
Sometimes when mortals come into contact with beings from the higher planes they give birth to children with features of those Outsiders. These special beings can be brought on by intercourse, a magical deal or pact, or merely excessive contact, depending on the being and upper plane involved.
Born of union between mortals and angels, includers half-angels and Aasimar.
Born of union between a mortal and a being from Anserak or other lower plane, most often a demon. Includes half-demons and Tieflings.
Born most often not of union between a mortal and a being from an Elemental Plane, but from excessive exposure to mana from those planes. They take up many different forms.
The Serpentborn manifest most commonly amongst Nereids, though it's not unheard of amongst others; a result of union between Naga and mortals.
A rare thing born when a pregnant individual has been exposed to the Void. This includes five variations for which there are not currently proper names.
Index of Races to return to the race links or Outsiders to have a look at the denizens responsible for existence of the plane-touched.