I hear the sounds of distress and come running to see what happened. In an instant, my extensive forensic training (via true-crime novels and television shows) kicks in, and I begin to process the scene.
Step 1: Interview the victim and the witnesses.
I don't expect to learn much from this part of the investigation, and my veteran instincts prove to be correct. What follows is the official transcript of our exchange:
Mommy: (to victim) "What happened, honey?"
Mommy: (to witnesses) "Who did this?
Witnesses: *crickets chirp*
Step 2: Examine the scene.
I have responded quickly enough to ensure that the crime scene remains undisturbed. I observe that all three witnesses are standing in close proximity to the victim. Witness #1 is holding a car, witness #2 is holding a ball, and witness #3 is holding a night-night; the victim is empty-handed. Notably, the victim's arm shows a clear dental imprint:
Step 3: Process the evidence.
This is where my photographic memory comes in handy: I quickly compare the laceration to my mental dental map of the victim and each of the witnesses. My analysis not only rules out a self-inflicted wound, but it also allows me to identify (and sternly reprimand) the perpetrator within seconds.
Case closed! Can you figure out who holds the dubious distinction of being the first member of the Fab Four to bite a former wombmate?