"... I think because it affects everything."

"Everything everything?"

"If there are any exceptions," says Lynn softly, "I don't know of them."

"How do things grow, then?"

"Things grow by harvesting resources around them, and then re-purposing things in them to what they need."

"But why are there any resources still around?"

"Well, because the re-purposed resources are resources themselves. For other things."

"But everything's getting less and less resource-y. Right? Why isn't it done yet?" asks Astrid, still floating in the water.

"Yes. And it - takes quite a long time. There are lots of resources in the universe, thankfully."

"How many?"

"I'm not sure. Too many to count, I'd say."

"So there will be enough for things to grow for a long time before the universe has to stop for gas?"

"Yes. Longer than any of our lifetimes, I'd say. Unless yours happens to be measured in trillions of years."

"Maybe it is! I could be anything, we don't know."

Lynn snickers. "Indeed you could be. I hope so."

".... Possibly," says Lynn, carefully. "I sincerely hope not, though."

"Is there a way to tell besides waiting?"

"There probably is," she muses. "We should check that. That... Is a very important thing to figure out."

"I want to know."

"Me, too. We'll see if there's a way to find out. Okay?"

"Okay." Pause. "I can be a floating thing. Can I be a swimming thing, how do I do it?"

And Astrid carefully swims. She is not unusually gifted at it, but she manages the dog paddle.

That's perfectly all right! More graceful forms of swimming will come with time and practice. Lynn praises her successes and corrects technique when necessary.