No child is born evil. Some are born pyschopathic, all adult psychopaths started off as children. Whether this nascent psychopathy turns to violence and harm will probably depend on childhood experiences and who they associate with. Remember many, probably most people, with psychopathic tendencies lead innocent and blameless, if possibly selfish, lives, without ever harming anyone.
Hilltopgran, we do know something of their childhood. Both had a parent who disappeared when they were young. The girl's father just walked out of her and her siblings lives early in her life.The boys mother died when he was five. His father was an absent parent and the boy lived with relatives.
This crime happened because chance brought together to children with similar characteristics, which resulted in a partnership which, as has been said, was toxic.
Last night DH and I were at Glynebourne to see Mozart's Don Giovanni, on the way home we were discussing the character of the main character, an obsessive womaniser and came to the conclusion that he was a psychopath, a man who felt no emotions, and possibly was aware of it. The nearest he could get to feeling anything was through sexual relief, so he raped/seduced every woman who came his way - and then moved on. The similarities with this case struck us both. I find it significant that neither of these children was particularly moved by what they did, the horror could not reach them - and afterwards they had sex.
I do not know what can be done with these children. Psychological and psychiatric advisers will be involved in the process leading up to sentencing. But sentencing children like this, think Mary Bell and the two young boys who killed Jamie Bulger, is very difficult. Mary Bell seems to have transitioned out of her childhood torment and behaviour to a balanced adult life, but one of the Jamie Bulger killers has been recalled to prison several times for various reasons.
Cases like this will arise from time to time, but they are very few and I think inevitable, many of the children involved have troubled backgrounds, but so do too many many children, and they do not do anything like this, but neither of the children who committed this crime had shown, outwardly, any behaviour problems that could foretell to just what lengths their behaviour would take them.