"Thanks," she says. "Have a safe trip home."
No one is panicking about Katie's lack of thumpiness, so neither does she. She goes back to toybox-rummaging and starts to make things out of legos.
It having been previously established that Katie does not think of legos as food, Chris keeps an eye on her but doesn't interfere.
Katie makes a lego bowl, and lego approximations of flowers, and a lego castle.
Katie makes a lego stirring rod, and attempts to stir the flowers around in the bowl. It doesn't work very well; she giggles when her stirrer breaks.
The list of unfamiliar words contains mostly nouns, and while many of them are relatively advanced - or archaic, given the source material - words, some of them aren't especially. She had to look up "aneurysm" and "Mormon", but she also had to look up "blood" and "cigar".
"Blood" is certainly the weirdest gap in Katie's vocabulary, but she was also pretty thoroughly devoid of knowledge of geography, apparently. She made a confused note about "hunting for food" - nothing Katie eats runs away and she hasn't seen anyone's carnivore entrées in a motile state - and she also had to look up "married" and "horse".
Eventually - during an apparent lull in legoing - she asks, "Katie, can I listen to you not thump?"
"Okay!" says Katie, abandoning the legos to go over to Chris.
Katie does indeed not thump.
She listens to herself, to double-check, and verifies that the stethoscope does indeed transmit appropriate thumping.
"Huh," she says.
"It's good that you're alive. But something weird is clearly going on, and I don't know yet if it's an okay thing or not."