So, Nancy Lanza was a doomsday "prepper" & survivalist:

[Catherina]

35. She warned the babysitter not to turn her back because Adam could get seriously hurt

She warned the babysitter not to turn her back because Adam could get seriously hurt and and not feel any pain. It's why the school watched him closely when he played baseball with the other kids.

A “longtime” family friend said Lanza had a condition “where he couldn’t feel pain.”

“A few years ago when he was on the baseball team, everyone had to be careful that he didn’t fall because he could get hurt and not feel it,” said the friend.


http://www.nydailynews.com/new-york/adam-lanza-20-deeply-disturbed-kid-article-1.1220752

In an interview with the news wire, Richard Novia, the advisor for Newtown High School's technology club said of Lanza's condition: "If that boy would've burned himself, he would not have known it or felt it physically."

http://www.businessinsider.com/why-adam-lanza-could-not-feel-physical-pain-2012-12

I find some of the responses here unbelievable. Plenty of parents tell babysitters not to turn their backs on their kids when they're paid to watch them. You can bet your sweet ass if my 9 year old couldn't feel pain, I'd tell you not to let him out of your sight.

He also had mental issues where any parent would want the baby sitter to be paying attention.

He recalled meeting with school guidance counselors, administrators and with the boy's mother, Nancy Lanza, to understand his problems and find ways to ensure his safety. But there were other crises only a mother could solve.

"He would have an episode, and she'd have to return or come to the high school and deal with it," Novia said, describing how the young man would sometimes withdraw completely "from whatever he was supposed to be doing," whether it was sitting in class or reading a book.

Adam Lanza "could take flight, which I think was the big issue, and it wasn't a rebellious or defiant thing," Novia said. "It was withdrawal."

http://www.google.com/hostednews/ap/article/ALeqM5jqFo4gzH05O-U4ILHjw4rODKwF2A?docId=26dd825803b1440087624a76620f186f

There's no need to exaggerate and try to make him out to have been a monster at 9 years old.