I asked both Josh and Zoë to sit at their table and wait while I finish preparing their lunch. Because they were hungry and they knew what was coming, they literally ran to their table and sat down. There was a book lying on the table and Zoë just swept it off to the floor to clear out the space in front of her.
Before I could say anything, the following "conversation" took place:
Josh: You're a litterbug, Zoë.
Zoë: NO! (With a petulant glare at Josh).
Josh: Yes, you are.
Josh: You're a litterbug, because you "littered" the book on the floor.
Zoë: No, KoKo 'bug!
At this point, I couldn't contain myself and just burst out laughing.
All the while, I was watching the two of them sitting there on opposite ends of their table, facing each other, like two debaters arguing a point.
Zoë might not know what a litterbug is, but she could sense that it was not a nice label and promptly fought back. I don't have to worry that she won't be able to hold her own. She's definitely a feisty one, our girl.