It has always annoyed me that kids get special treatment when it comes to on-screen violence. I'm not a gorehound by any means, but it can get downright silly sometimes. If you want proof, just go and throw Natalia off the crane in Revelations 2, and see what it says on the screen: "Fainted." Seriously??
There used to be a car commercial showing a cat being decapitated by the car's closing roof. As a cat lover, I found that extremely distasteful, especially since everyone around me apparently found it funny, and a commercial like that would never have made me buy that car, even if I had a driver's licence. I wouldn't have had the same reaction if that had been a scene in a horror movie about machines coming to life and killing everyone, or something like that, it always depends on the context. So in the context of an apocalyptic game or movie, it should be expected that children can die, too, instead of magically surviving everything unscathed no matter the odds.