Luke: Mommy, there's an X in the sky.
Me: You're right, there is an X in the sky, neat!
Luke: How did it get there?
Luke (again before I could answer): An airplane made it.
Me: Wow Luke, you are right, an airplane did make it.
Luke: With its engines!
Me: Yes Luke, very good, an airplane made it with its engines!
Luke: No mommy, an airplane made it with its jet engines.
My child is a genius!!!