Lou describing a Fat lip

As most of you know, I homeschool my children. This is our first year and we use Sonlight curriculum. Well, a few weeks ago in Language Arts, the main focus was on the the short "a" sound. The sentence she had to read, trace, rewrite, and use to learn the parts of a sentence was: The lad had a fat lip. We discussed the word lad and she decided that the word boy was "much better". When I asked her which word described the lad's lip, she answered fat. But when I asked her how she thought he got a fat lip, her imagination took over...

and I quote from Lou:

"Someone was holding the boy's lip out and all these rocks were falling down and going ppfffhhhttt on his lip. When the rocks went ppppffffhhhttt on his lip, it cracked it open and made it bleed and get a bruise and then get fat."

Me: staring in disbelief, but laughing hysterically inside. "Oh, I thought he might have fallen down while playing."

Lou: looked at me like I was saying something odd.

We just moved on in the lesson: Which two words in the sentence rhyme?...

The imagination of Lou is something I am having a hard time keeping up with these days.