A splinter in the McBaby's foot! And it was my fault. I was wearing an oven glove and pretending to be a monster. As you do.
I remember saying "don't get splinters" but I didn't actually do anything about it. So as a direct result of my negligence, I had to get a 2cm splinter out of his foot while he repeatedly kicked me in the face and threatening to put me on the naughty step.