Tooth & Nail

Yesterday I noticed that Garrett's fingernails needed to be clipped.  You may wonder why that is a notable event.  I haven't had to clip them for several years because he has kept them bitten off.  While I was clipping them, I asked him what had made him stop biting his nails.  He looked at me in puzzlement and then it was as if a light bulb went on in his head.  "My tooth!!!" he exclaimed.  Of course.... He lost his first tooth a couple of weeks ago and it was the bottom tooth he used to bite his nails with.