Divine punishments of opressing tribes?? All of them even kids?

Well, we have a lot of stories in holy Qur'an about tribes of different prophets who were misguided and oppressor, finally when disappointed of their guidance God sends down a punishment and everyone dies except believers. (E.g. Prophet Noah's tribe) It doesn't explain but I assume the whole tribe is punished, right? Is that also the case for the kids of the tribe? If yes, how can we explain this?