Out of all the Friday the 13th films, this one is especially ill-suited for children. You might not think that since the main character, Tommy Jarvis, is a really cool kid who pulls off the remarkable feat of chopping Jason Voorhees into what would probably be a very expensive Japanese delicacy. In that sense, it's kind of a rally cry for little kids everywhere.
But that ignores the idea that Jason first kills Tommy's mother. This is unsettling not just because it's really scary for a kid to lose their only parent, but because Jason seems a lot less fun when he's taking out innocent single mothers. That's probably why her death occurs offscreen. Otherwise the little kid inside all of us would be scarred.
