Bartleby.com states the following:
Quotation: When an opponent declares, “I will not come over to your side,” I calmly say, “Your child belongs to us already.... What are you? You will pass on. Your descendants, however, now stand in the new camp. In a short time they will know nothing else but this new community.”Attribution: Adolf Hitler (1889–1945), German dictator. speech, Nov. 6, 1933. Quoted in William L. Shirer, “Education in the Third Reich,” ch. 8, The Rise and Fall of the Third Reich (1959).
You will have to take the book out of the library, because I cannot find the text on line.