I remember that. People were pissed off that you couldn’t kill children in Fallout 3, they disabled combat in that town. But the main difference there is that when you grew up enough, the rest of the kids threw you out of the town and you weren’t allowed to return.
Cixin Liu of Three-Body Problem has a novel with a similar premise, Supernova Era. A distant Supernova washes the Earth with radiation that will kill off everyone over 13. So it’s a desperate race to teach children how to keep the world going before they die.