I have 2 dc, the eldest is 5.5 so probably about to start losing teeth. Iabu in planning to tell them there's no such thing as the tooth fairy? It just seems a bit much really, and quite a lot of effort to maintain the lie! When I was little the tooth fairy used to be quite unreliable, often leaving the tooth under the pillow for a few days- I suspect it might be similar nowadays.
Obviously I'm a total hypocrite as we have done Father Christmas and love the magic of that. But, I soon put a stop to the bloody Easter Bunny at MILs house!