Them being annoying obnoxious selfish shits is pretty accurate for a lot of children though. As is getting no consequences for whatever they do, though that's more a current day thing than a medievalish one I guess.
Inability to kill them is probably just to minimize controversy upon release, but it probably won't be long after until there's a mod for it. Back in the days of Fallout 2 pickpocketing brats was so easily handled by having an inventory containing nothing other than a ticking explosive and standing in front of them, no mods required. How times change.
