Deep Science Questions in Fifth Grade

Today, as I was teaching my fifth graders, I was priding myself in my effective teaching of matter and how it "can neither be created nor destroyed." The entire class seemed to have a solid grasp on the concept and everything was going along peachily............until Kyle raised his hand and asked, "but Mrs. Mohlman, when we make babies, isn't THAT matter that is being created?" Now, let's put this on pause for just a second. What would YOU have answered if you were given a split second to think of an answer when 31 students are staring at you and asking, "Yeah! What about that?" That's right...your response wouldn't have been any better than mine was. "Uh....ask your mom!" In all honesty, I thought of a million great answers to his questions later, many of them involving mitosis and meiosis. I guess now the thing to do is be the responsible teacher and call him back tomorrow to explain why matter is still not being created, as to not scar him for life because his teacher didn't care enough to answer his questions. But who knows, by tomorrow morning he probably will have already forgotten he even asked,