Are stepchildren over-represented as victims of lethal parental violence in Sweden?

Evolutionary psychologists have suggested that stepchildren should be over-represented as victims of lethal parental violence compared with children living with their two genetic parents, because of relatively more lapses in parental solicitude among stepparents. In our study, using data over a period of 35 years in Sweden (1965-1999), there was no overall over-representation of stepchildren as victims. For very young stepchildren there was a tendency for over-representation. In families with both stepchildren and children genetically related to the offender, genetic children tended to be more likely to be victims.