Mommy, I hurted myself!

So I'm in my bedroom, minding my own business, when I hear Eddie cry out, "Mommy! I hurted myself!"
Being a relatively caring mother, I inquired how he hurt himself. I was expecting either a screaching condemnation of his brother so that I could tell Chas not to hit, kick, pinch, punch or look at his brother with furrowed brow, whichever transgression he was accused of. Or I would simply be given a body part to kiss better. No. I got the following description. It's not absolutely verbatim because it took me a while to get in here to write it down. But it is the gist of how Eddie got hurted.

"I went potty so I had to wash my hands but when I went to wash my hands I saw my really good puzzle and I stopped to look at it and there were cars on it so I picked the cars up and when I throwed them off of my puzzle one of the cars bounced off the box and it came back and landed on me there (points tearfully to his toe)."

This never happened to him when he wore diapers.