No more Tooth Fairy

My oldest child is quite inquisitive. If you want to call it that. She is into everything.  She always has been. She wants to know why for everything. It is most often a good thing because she is very smart. It can also cause problems though. Today is a problem day. I am camped out on the couch due to some cramping I am having so she took that as an invitation to snoop. She went through my jewelry cabinet. I keep things in there that are important. Among those things are her baby teeth. She came into the living room carrying a little plastic tooth with her two incisors in it. She kept pestering me about why I had teeth, whose they were, why did they look like hers. So I gave up. I told her I was the tooth fairy. Then she got mad.  She wanted to know if her dad knew that I was tricking her. I tried to explain that we did it to add to the magic of child hood.  She got more angry, started stomping around and yelling. I sent her to her room.I explained the importance of minding one's own business and not looking through other people things.  She is just mad. I really hate it. What else could I do. She is 9 1/2  after all.