ribs do kind of look like gills

On Sunday E and I went to the neighborhood park, and we ran a lot, played tag. E ran so hard she had to stop: she put her hand on her ribs and said she had a pain in her gills.

I said, "That's actually called a 'stitch'," and I told her to rest for a bit and it would go away. Every time after that when she was running and had to stop, she would grab her side and yell, out of breath but apparently quite happy, "My ditch! My ditch!"