Kathleen Heide, a criminology professor at the University of South Florida in Tampa, has studied the phenomenon for decades. And by studying FBI crime data from 1976 to 2007, Heide estimates there were more than 1,900 cases nationwide of children 17 and under killing a parent.
What makes the Burlington case unusual is that it may have involved attacks on parents as well as younger siblings, said Heide, who wrote a 1994 book titled, "Why Kids Kill Parents." She said motives generally differ between attacks on parents and attacks on siblings.
In cases of a child killing a parent, Heide said, perpetrators often are motivated by fear or terror, a protective instinct for another parent or a sibling, or a sense that a parent is getting in the way of inappropriate behavior. Other factors include mental health issues or adverse reactions to a drug, Heide said.
In attacks on siblings, motivations can include rivalry or jealousy and a desire to strike at a parent through the death of a child, Heide said. But she added that such attacks are rare because of the prevalence of strong bonds between siblings and, in the case of younger children, their vulnerability.
"It's such an usual event and it's such an extreme event," Heide said of the initial allegations in the Burlington case.
Friends and family described the boy as a good kid, more outgoing than his peers, someone who would volunteer at Evangelical Free Church as a greeter, hand out church bulletins, help with audio and visual equipment and run PowerPoint presentations during services. He helped other children with their Bible verses.
Wally Long of Springfield, Mo., said he spoke with Charles, his brother, at least once a month and that there was no sign of trouble in the home, where Marilyn Long homeschooled the children.
"They loved their kids tremendously. It was their life. I mean, they have seven of them," Long said in an interview with Denver's KMGH-TV that was distributed to local media.
"Their life was wrapped around their kids."
"People have a very difficult time understanding what happened," said Paul Mones, a Portland, Ore., children's rights attorney and author of the book, "`When a Child Kills