I think the reason for it was already broached before the thread was necro'd. Killing children is censored in many countries, like when Fallout had to remove all of them in Europe.
Man, I remember they made a goddawful abrupt job about it, too. Children were just made invisible while their ghost-chatting was still visible in several areas and few quests that involved finding a child or similar stuff got broken. Of course an unofficial patch could be applied to solve the issue, but still.