Who would report it? If parent kill their child they are unlikely to, if someone else kills their child they are likely to. > From the evidence I have gathered

Who would report it? If parent kill their child they are unlikely to, if someone else kills their child they are likely to. > From the evidence I have gathered from primitive societies What evidence are you referring to? Also, again "unthinkable" is different from it not happening. In fact, it makes it even more likely to be covered up, if people don't care to investigate, or otherwise want to know.