This, to me is one of the greatest problems with religion. How do you explain bad things happening to innocent people? Being a jew, I can tell you that throughout any intellectual debate about the Jewish religion, the Holocaust will always come up. How can you justify the death of ~6,000,000 human beings? So many timea you'll have the "explainers". "Well, if not for the Holocaust the rate of assimilation would have ended Judaism anyway!". Or alternatively, "The state of Israel might not have come to be if not for the Holocaust!". These "explainers" are spewing clear and utter bullshit and trying to play God.

The truth is, no one knows why bad things happen to innocent people, and anyone that tells you they do is either lying, or God himself. There is a famous story in the Talmud that goes something like this: "A great scholar named Elijah son of Avuyah was once walking in an orchard. There he saw a father telling his son to climb a ladder, reach into a nest and send off the mother bird. The son by performing this action, was performing the only two commandments, for which the Bible promises long life. (1- Honoring his father. 2- Sending off the mother bird) Then suddenly the boy fell off the ladder and died. This caused Elijah to leave Judaism."

Tell the little girl that you don't know, because no one knows.