The human body is weird, "normal" means little, and the course of thriving never did run straight. Current example: The Snaggletooth.
Let me explain what you're seeing here. The child (name and face hidden at her request, though she allowed me to take a picture) has two front teeth coming in, but the baby teeth have not, and will not, fall out. Also, the adult teeth are diagonal to each other: the one on the left in the photo is coming in behind the baby tooth, and the one on the right is coming in above and in front of the baby tooth. The baby tooth on the right has also not fallen out; it is almost horizontal, and wedged in so tightly that it doesn't wiggle. Look closely and you can see the root, right under the adult tooth.
Now this is all very visually startling. But I took her to the dentist -- not even a regular cleaning; I actually made a separate appointment -- and though he was rather taken aback and said he'd never seen anything like it, it's apparently okay for now. Pulling the tooth, at the price insurance would charge for it, is counterindicated (though if someone jostled it loose at home, that would be fine). Snaggletooth is understandably wary of people threatening to pull her tooth, especially her older sister who rubs her hands together with relish and talks longingly of the pliers.
(I don't let anyone tease her about pulling it; it's a tender topic with the youngster, naturally.)
The dentist says that the adult teeth are going to come in how they're going to come in, and the baby teeth won't affect that. All well and good. The bad news: now I have one more slated for the orthodontist. I hope he enjoys his luxury house and car that we've financed for him over the years.
The great excitement of the house was that Snaggletooth suddenly lost a tooth the other night. We all dared to hope... but no, it turned out to be that little gap you see in the bottom, a tooth no one knew was even loose. Ah, how tricky it is to be six!