Meg is pretty sure Jonathan isn't a potato

It all started when Meg knocked on the bathroom door.

Jonathan called, "Nobody here but us chickens!"
Meg: "There aren't any chickens in there."
Jonathan: "How do you know anybody is in here? Maybe I'm just a potato."
Meg, giggling: "You're not a potato!" Then she stopped giggling and said, very firmly, "And I WANT TO GO POTTY."