3000 kids are killed every year...
You will have to define what age "children" encompasses. The FBI uniform crime report might be useful. There are many causes of death for "children" that are in front of firearms.
Unknown. The FBI Uniform Crime Reports shows crimianl activity. DoD shows uniformed service members.
1500 children are being murderd by abuse each year all over the world
I'm sure it varys from county to county.