The babysitter arrives after breakfast. She rings the doorbell, and Lizbeth lets her in.

Katie had romaine for breakfast. She peers curiously at the babysitter, the last half-leaf in her hand; she isn't sure yet if she wants to finish it or not.

"Hi!" says the babysitter.

"Hi! Are you the babysitter?"

"I'd better be!"

Lizbeth giggles.

"Virginia! Hi," says Chris. "Thanks so much. Katie, meet Virginia. Virginia, this is Katie."

"Hi, 'ginya," abbreviates Katie. Her accent is fading, some, but it still trips her up occasionally.

"...Can we compromise on Gina?" she inquires.

"Gi-na. Okay."

"Thanks."

"I'll leave you to it," says Chris. "Bye, everybody."

"Bye! Have a good time at the DMV!" calls Katie, waving.

She laughs as she walks out the door.

"All right," says the recently renamed Gina, "who wants to watch me do my math homework?"

"Me!" says Lizbeth.

"Okay!" says Katie, who doesn't know whether math homework makes a good spectator sport but is willing to try it on Lizbeth's say-so.

Virginia laughs. She goes to sit on the couch, and lets Lizbeth sit on one side and Katie on the other while she opens her textbook and starts doing algebra.

Katie watches for about ten minutes, waiting for this to become interesting, then says, "I'm bored."

"I'm not," says Lizbeth.

"But this is boring."

"Not to me!"

"Yes, well, not everyone is a tiny mathematician," says Gina. "What do you want to do, Katie?"

"I want to play. Or go outside."

"You can play in this room," she suggests.

Katie slides carefully off the couch, and makes her way to the toy box, which she starts sifting through. She picks up a long Y-shaped toy she hasn't investigated before. "What's this?" she asks.

"A stethoscope."

"What does it do?"

Katie watches. "Hearts make sounds?"

"Oh, all right."

Up she goes.

Katie follows her and watches.

She listens to Virginia's heartbeat thumping along for a while, then disentangles herself from the stethoscope and offers it to Katie. "Wanna try?"

Katie takes it, imitates the way Lizbeth was wearing it, and attempts heart-listening.

Thump-thump. Thump-thump.

Katie listens to Lizbeth too.

Thump-thump, thump-thump!

"Oh? Let me see," says Virginia, holding out her hand for the stethoscope.

Katie hands it over. "I didn't hear me thumping. Does it not work on yourself?"

"...I'm confused," says Virginia. She looks at Katie. Yes, this is definitely a child who appears to be alive. Moving around, talking, sitting up, not obviously sick or in pain in any way.

"It's not broken?"

"It doesn't seem to be," she says. "It's also not picking up a heartbeat from you."

"I don't go thump?"

"You do not go thump."

"Is... that okay?" asks Katie, peering at Gina's face.

"Not usually," she says. "Until today, I thought that the only people who didn't go thump were," she simplifies a little to avoid alarming the three-year-old, "dead. But you're perfectly alive."

"I am alive. Are you sure I don't thump?"

"Gina, if people who don't thump are dead and I am alive and don't thump does that mean I will not ever die?"

"...Probably not. People who are dead also don't move around or breathe or talk or eat, and you do all of those."

"I want to not ever die, though."

"Yes," says Virginia, "that would be nice."

"Why don't I thump?"

"I have no idea."

"Will Chris know?"

"I hope not," she says before she can stop herself.

"Huh?"

She shakes her head. "Never mind, sorry. I'm just very confused. And I wouldn't like it if I found out that Chris knew all about this and then didn't tell me."

"Why would she have to tell you that I don't thump if she knew?"

"Part of what a babysitter does is make sure you're safe," she explains. "Whatever the reason is why you don't have a heartbeat, it means that you don't work the way most people do, and not knowing anything about that means I might not be able to do my job. So if Chris knows, it would be irresponsible of her not to tell me."

"I bet she doesn't know. I never played with that thing before. And I came from a basket."

"Okay," says Virginia.

Lizbeth watches them both thoughtfully.

"What?" Katie asks Lizbeth.

"I dunno."

"Do I have to start thumping, Gina? I don't think I would like to thump."

"...Could you start thumping if you tried?" she inquires. At this point she is willing to believe it might be possible.

"I don't know how to try to thump. Are you trying?"

"No. Everyone else just does it without trying, and we couldn't stop if we wanted to, and if we did stop we'd die."

"I don't think I can start, then."

"I didn't think so either, but I wasn't sure."

"Okay. But I don't seem to have to thump to be alive."

"Yes," she says.

"That's okay then." Katie takes the stethoscope and goes to listen to the fridge.

Virginia shifts so she can see into the kitchen from where she's sitting, and pays attention to Katie while she does her math homework. Rather more attention to Katie than to the math homework, in fact.

Katie listens to the fridge, and the microwave, and then she lets the microwave go empty for five seconds and listens to it while it does that, and then she listens to the kitchen window.

Eventually Katie is bored of the stethoscope. She puts it back in its box and goes to sit by the window and look out at the sun.

"Please don't look right at the sun," says Virginia. "Doing that can hurt people's eyes, and you can't always tell right away how hurt they are."

"But Giiiina, I like the sun," says Katie, turning to look at Gina. "It's bright and it's pretty."

"You can look at other bright pretty things," she says. "But not this one, because it might hurt you."

"It doesn't hurt to look at though."

"It might still be doing bad things to your eyes," says Virginia. "The only way to know for sure that it isn't would be to keep doing it and see if you go blind. I'm not going to let you do that, because I don't want you to go blind."

"Oh. I don't want to go blind."

"So don't stare at the sun."

"What if it's like thumping?"

"It might be like thumping," she says. "But I'm not sure it's like thumping. And I don't know a safe way to find out. Staring at the sun is not a safe way to find out."

"I hope it's like thumping. I like the sun."

No response from Gina.

Katie starts browsing the bookshelf.

...Gina observes this.

Katie picks out a book she hasn't looked at before, and hoists herself up onto the couch where she was previously sitting, and reads.

...Well okay then.

Katie pages very slowly through the book, but she does appear to be really reading this omnibus collection of Sherlock Holmes stories.

As long as she's having some approximation of fun, Gina decides not to make a fuss.

Eventually Katie goes and gets a slip of paper and starts writing notes on all these characters and the clues that have turned up.

Katie will continue until interrupted or distracted.

"Me! I'm hungry!" says Lizbeth.

"I will eat some food," nods Katie. "I can only eat food, I won't eat not-food like Lizbeth and Chris eat sometimes."

"Okay," she says. "You can eat what you want, and Elizabeth will eat what she wants."

Katie eats spinach until her bowl is empty and then she goes back to her book, apparently satisfied.

"If you get hungry again later I can get you something else," says Gina.

"Okay," says Katie. "I don't get very hungry though."

"...Okay," says Virginia.

Katie is not done with this book yet. She continues on. She is accumulating a list of words she does not know.

Virginia goes back to entertaining Lizbeth with her math homework.

Eventually Katie puts down the book and gets the dictionary to look up the confusing words.

At this point, Gina is not especially surprised.

Katie re-reads the pages on which she found those words. (She noted the page numbers.) Then she continues.

Well, that's... systematic.

She is very systematic! Eventually she has finished a couple of Sherlock Holmes stories. She puts the stories and the dictionary back where she found them, and then looks at the math homework to see if it has become any more interesting.

It is exactly as interesting as it has been all day.

"This is boring. Why are you doing it? Is it just because Lizbeth likes to watch it?"

"I don't think it's that boring," says Gina. "And I have to do it for school."

"Why?"

"Math is important to know at least a little bit of when you're a grown-up, especially if you're going to be doing things that need it," says Virginia. "So we have to learn it in school, and doing homework helps us learn."

"What things need it?"

"Architecture, engineering, finance. To name a few."

"Do you want to do one of those?"

"I'm not sure yet."

"How will you pick?"

"I'm going to find out more about everything I could do first, before I decide anything."

"What else might you do?"

"I'm not sure yet," she says. "And I haven't started keeping a list, because I don't know enough about all the possibilities."

"I like lists. I made a list of food."

"I saw."

Ho hum. Katie goes looking through the toybox again.

Some time later, Chris can be heard opening the door.

"Hiiii, Chris!" calls Katie. "Gina says I don't thump!"

"Can I get that in plain, understandable English, somebody?"

"...Is that so," says Chris.

"I am alive anyway," says Katie reassuringly.

"That's good to know."

"Yep! I like to be alive."

"I like you to be alive too," says Chris.

"Me too!" says Lizbeth.

"Do you thump?" Katie inquires of Chris.

"Yes," says Chris. "I thump."

"I wonder how come I'm the only one who doesn't."

"I wonder that too."

"How do we find out?"

"I'll think about it."

"Okay."

"Bye," she says. "Bye, Elizabeth. Bye, Katie."

"Bye, Gina!"

Out she goes, laughing.

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.

Cute. And interesting. And cute.

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.

Lizbeth giggles, too, looking up from Katie's list of unfamiliar words.

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".

Looking at it was just an idle thought, but it is actually fascinating and Lizbeth is now studying it in earnest.

"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".

Katie, obliviously, plays with legos.

"Okay!" says Katie, abandoning the legos to go over to Chris.

"I am alive anyway," Katie reminds her, "so it's okay."

"...In a sense," she says, "yes."

"In a sense?"

"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."

"...Am I sick?"

"Probably not. I don't know of any way to be sick that involves having no heartbeat and being otherwise fine."

"That's a very good question and I wish I knew how to answer it."

"What is thumping for?"

"I looked up blood in the dictionary. It wasn't very helpful."

"What did it say?"

"It said it was a fluid in animals that does - things, but we aren't animals, are we?"

"Some people don't like to think so, but we are the kinds of creatures that have blood. At least," she looks at Katie contemplatively, "the rest of us are. I'm getting less sure about you."

"How do we find out if I have it?"

"There's ways," says Chris. "I'd consider these a sign." She shows Katie the blue veins on the insides of her wrists. "They are veins. They contain blood. It's red when it has oxygen in it, blue when it doesn't. Let's have a look at your arms and see if we can find any."

"Ew," says Katie. "Does it have to be a big hole?"

"Nope. Tiny ones work just fine. Better, actually, because if we leak too much that is generally considered very bad for us."

"I want to know if I have blood. The hole goes away later? Right?"

"On people with blood, it does. Usually pretty fast, if it's a small one."

"What about if you make holes in other kinds of alive things, though?"

"In any kind I can think of, the hole goes away. Maybe not as fast in some cases. And some kinds of alive things are too small to poke holes in very easily, so I wouldn't know about those."

"Okay. Can you do it? I don't wanna look."

"Yes..." says Chris. "I can. But I think I'd rather not do it now. There are things specially designed for safely poking small holes in people to get a little bit of blood, and I don't have any in the house, but I can get some."

"Oh. Okay."

"So I'll do that next time we run errands."

"There might be, but until we find out about the blood, I'm not sure what."

"Okay." Pause. "I'm not empty."

"Even people with blood have plenty of other things in them too," says Chris. "Bones and muscles and organs, for example."

"Do I have those?"

"Harder to check. There's a way to look at someone's bones without doing any gross or harmful things, but it needs expensive equipment I don't have."

"This sounds complicated. How do you know everybody else has blood?"

"I haven't personally checked. But I've never heard of anyone else who didn't. And it would be hard not to notice, and if someone did notice and didn't decide to hide it, a lot of people would get very excited and we'd hear about it almost for sure."

"It should probably be a secret. Otherwise a lot of people will get very excited about you, and some of them might not be nice."

"Lizbeth and Gina are both sensible people and I don't think they'll be telling anyone."

Hugs!

"...Euagh?" says Chris, pausing in the act of removing the wipe from its little square packet.

"Do I have to touch it? I don't want to touch it."

"The purpose of the euagh is to make your skin clean so that when I poke a hole in it, nothing gets in that could make you sick. So yes, you have to touch it. But not for very long."

"Can't I just wash my hands?"

"I'm pretty sure the euagh is better at getting things the right kind of clean than washing your hands is. But if you really don't want to touch it, yes, you can just wash your hands."

"I really don't want to touch it. It's not for touching." Katie gets up and goes to the bathroom and washes her hands and comes out again. She looks suspiciously at the euagh.

The euagh has been returned to its packet and partly folded up, and what little of it remains visible is looking very nonthreatening.

Katie holds out her hand, satisfied that she won't have to touch a thing that is not for touching.

Chris gets out a lancet and carefully pokes Katie's finger.

"Flowery?"

"It tastes like flowers smell. And sweet."

"...Okay," says Chris. "I did not expect that."

"I'm... not completely sure," says Chris. "Mostly because I can't think of an explanation that makes any sense."

"I don't look like a flower," says Katie.

"You don't!" she agrees. "You look like a person. But most people bleed blood, not... sugary flowery stuff."

"Well..." Katie ponders this. "Why do you do that? Maybe something got in the way of my why."

"If something did, I have no idea what or how or exactly what it would've gotten in the way of," says Chris.

"Huh."

"Evidence seems to loosely suggest that you're a plant, because those don't have heartbeats and do leak sweet flowery stuff if you poke holes in them. But I have no idea what that would even mean, because as far as I know, plants aren't the kinds of things that get up and walk around, or think or talk or come in people-like shapes."

"How do you tell for sure if something is a plant if you don't know?"

"I'm going to have to think about that one," says Chris.

"Okay... I wanna go outside."

"Okay."

Yep, that does appear to be a thing.

Katie comes back in at sunset. She has strawberries for dinner, leaves and all.