My dd is gentle with her toys and really treasures them. My ds is a little wild--age? Typical boy behavior? I don't know.
An xfriend of mine has a son, who at three, actually set the house on fire on purpose. When we were together, I watched her scream at her son and call him horrible names. She told him he was totally worthless. Yes, in front of a playgroup. I have also watched another mom slap her son hard (leaving a mark) because her one son was hitting the other son. My kids squabble now and then, but never hit each other. I no longer associate with this playgroup anymore--and these are really upscale well-to-do community members--not criminals. But their kids kind of worry me.
Any connection? I don't know. But I do know this--if these types of things are chalked up to "kid behavior" now--and they very well could be kid behavior--at some point in time the parents have to understand that not all kids act like that and that at some point, if the behavior continues, they need to do something--maybe actually take actions to help them understand how to deal with their frustration (if that's what it is)--or how to channel their issues in a more appropriate way (like leave the room if frustrated with a toy instead of ruining it). You know: OK Johnny, I see that you are frustrated with your car, but let's try walking away from it instead of destroying it, so that when you feel more calm, you will still have it. Good job, you did it! Afterall, isn't that what parents are supposed to do?
Oh, and don't discount modeling--because I think kids learn by what is modeled in the house--which is my whole point of this post.