Eldest lost his first baby tooth sometime overnight or this morning. We're not quite sure if it came out during the night and he swallowed it, or it just fell out and he didn't realize it this morning, because we can't find the tooth (never fear, we left a note for the tooth fairy). He noticed it was loose Saturday, and was excited, then a little spooked by the concept, then excited again. Yesterday, the tooth was wiggling both back and forth and side to side, so it was just a matter of time.
I'm surprised how young he lost his first tooth -- he just turned 5 in December. I didn't lose my first tooth until just after 7 (of course, I was smaller at 7 than Eldest is at 5). It's a memorable little milestone; we just have to hope he doesn't swallow the next one that falls out.