Theology with a Six-year-old

Despite the fact that I have a graduate degree in the subject, we don't talk about religion much with the kids or try to structure their beliefs in any formal way. For this reason I'm always curious about what they think about the subject when it comes up. This week, I had a great car conversation with Ellis that started out about allergies and ended up as a theological inquiry:

Ellis: "If you didn't have an immune system, you wouldn't have allergies."
Me: "Yes, but if you didn't have an immune system..."
Ellis: "You would die. And when you are dead you don't have an immune system."
Me: "That's true. When you die eventually you don't have anything left."
Ellis: "Yeah, the only thing left when you die is your spirit."
Me: "What happens to your spirit?"
Ellis: "It walks around. Like ghosts."
Me: "Do spirits walk around on earth or do they go someplace else?"
Ellis: "On earth."
Me: "Wow, how does everyone fit?"
Ellis: "Ghosts don't take up as much space. They can go through each other."
Me: "Do you think that ghosts are with God?"
Ellis: "Yeah, because all ghosts can see other things that are like ghosts."
Me: "Oh, so God is a ghost? Do you believe in God?"
Ellis: "Yeah, God controls the weather. He makes sure it changes all the time so that we don't get bored with the weather always being the same."