Some researchers of filicide dispute these statistics due to incorrect coroner rulings, inability to locate remains, etc. Also, the younger the victim the higher the statistic rises to include parental involvement. While the general statistics dictate 60% it increases exponentially the younger the victim. A study by Dewar states 80% of homicide victims under the age of one is killed by a parent. Under ones are at the most risk with preschool children the 2nd highest likely to be victims of filicide.
One thing that irks me about most national filicide statistics is that no distinction is made between natural and step-parents either. There really should be. JMO and FWIW
I agree that lumping parents and step-parents together in the statistics is very unhelpful! Also, the statistics obviously are only based on solved cases or cases where all the known relatives and friends have been cleared. I wonder how many toddlers' and babies' murders are unsolved?
What about cases like Caylee Anthony? Is she going to go into the "accident" column?
Based on cases that have come to my attention (mainly here on WS) I'd say parents are more likely to kill than step-parents. On the other hand, moms' husbands, ex-husbands, boyfriends, and ex-boyfriends are the most likely of all groups to kill toddlers.