Excerpt from Finding Life on Mars

I was six years old.
"Father, I think I am ill," I said, in my tiny, piping voice.
"Oh?" Merlin said. He set aside the solenoid he was working on and turned his full attention to me. We were in the kitchen and my memory informed me it was identical then and now. "Why do you say so?"
"Look," I said, and extended one hand, palm up. In the center of my palm lay a milk tooth. It had fallen bloodlessly out while I slept. When I awoke, my tongue found a gap in my gums, and I found the tooth on the floor under my sling.
"Oh, you have lost a tooth. How wonderful."
"Then I am not sick?"
"No, baby, the farthest thing from it."
"I am not a baby," I said. "Please explain."
"Well," Merlin said, "it is normal for a child of your age to lose her teeth, slowly, over the course of a few years. New ones are growing in, beneath your gum-line where you cannot see them, and eroding the roots of the old ones. The old ones fall out, new ones grow in. Perfectly natural."
"Why?"
"Well, because if you were born with a full set of adult teeth, your head would be too big to fit through the birth canal. And if your teeth were not replaced with larger ones, your adult jaw would be full of gaps."
"Oh."
If he had left it at that, it would have been better. Maybe a lot would have been different. But he did not.
"Now, where should we put the tooth? On Earth, we used pillows. You would leave a lost tooth under your pillow and the Tooth Fairy would find it, replace it with a few coins. Here we not only have no pillows but no beds. So where should we leave it?"
"What is a fairy?" I asked.
"My goodness, but we need some books to read to you. We never planned for children, you know. Let me see. Fairies are magical creatures that live in the woods and sometimes at the end of nice gardens. Mostly they are there for young girls to find beautiful, but sometimes they are mischievous. They steal or play tricks or cast naughty spells."
"There is no magic," I said.
"Can you be sure?" And Merlin reached behind my head, touched my ear, produced a solenoid. "If so, then how did this get behind your ear?"
"That's a trick," I said. "Not magic. There is no magic."
"You mustn't be so upset over it, baby girl. Magic is just something we talk about to have fun, to explain things we cannot otherwise explain, to wonder at the nature of the universe."
"I'm not a baby and there is no magic."
"Please, just calm down."
But it was too late for that. I started to shout. "You're a liar and there isn't such a thing as magic. You shouldn't lie to your children. Father Christmas is a lie and the Easter Bunny is a lie and God is a lie and the Tooth Fairy is a damned lie."
Merlin sat back, narrowed his eyes, crossed his arms. I knew I had crossed some kind of invisible line and I didn't know what it was, why it was. He didn't say anything, though, and I couldn't stop.
"If there is a God and if there is magic, then bring back my mother. Give her back to me!"