How Can Parents Do This To Their Own Kids?

A recent article from Reuters states that two Alabama children that were murdered by their own parents were tortured before they were killed.  This begs the question:  how could parents do that to their own kids?  If parents don't feel as though they couldn't handle their children, they could go to various organizations for help.  They certainly didn't have to resort to torture and murder to deal with their issues.  The parents are pointing their fingers at each other, but meanwhile, the body of one child is still missing.  At this time of year when love is supposed to prevail, unspeakable cruelty rears its ugly head.