It's important to remember that you are talking to a little kid

Me: Son, how did you get that cut on your eyelid?

4 year old son: Emma made me lie down and then she stepped on my face.

Me: ....uh....

We were a bit concerned that one of his classmates was making him lie down so she could step on him. As it turns out, after a bit of further discussion, what really happened was that she bumped into him, causing him to fall and then her foot fell on his face. Nothing intentional, just an innocent accident. Glad we didn't jump to anger when we first heard the story!