“You don’t need a playroom anymore,” Jack pointed out.

“No, but it could be some other kind of room. I always wanted a secret place up in the trees.”

“Sounds cool.”

“I doubt it’ll ever get done.”

After our snack, we went down to the dock. The air was warm. We settled in the green chairs. I was glad we had arrived at that time in the evening when there was still plenty of daylight left and the lake was turning into a calmer, more secret version of itself. Jack was quieter than usual, looking out at the water as if he were alone.

“Do you think,” I asked him, “I would be the same person if I hadn’t grown up with this lake?”

“You couldn’t know without rewinding your life and doing it again. I didn’t grow up with a lake.”

“And you survived.”

“You just have to guess,” said Jack.

“My guess,” I said, “is that after all these years the lake is inside of me. Not as in—cut me open and find a lake.”

“No.”

Out in the middle, a dark bar drifted on the silvery surface. I knew what that felt like. You laid your paddle across the canoe and stopped trying to steer or control it, or wonder which way to head next. Let the water decide.

“Do you know what it’s like here in the winter?”

“Awesome, I bet.”

“It is so, so beautiful. You should hear the sound the lake makes. It’s the most unbelievable sound. Like this enormous thing, like an airplane, is under the water trying to turn over.”

“Is it the ice cracking?”

“Not cracking. I don’t think it’s cracking. Shifting, maybe? Or trying to break away from the shore?” I knew it would be impossible to impress on Jack the sound made by the frozen lake. You had to hear it for yourself. “Next winter you have to come up.”

“Sure,” said Jack. “Let’s.” A bird went by, so high it didn’t make a sound.

“Do you ever pretend,” I said, “that you’re looking at yourself from outer space?”

“Sometimes, yeah.”

“Or else looking at yourself from the point of view of something under a microscope?”

“A thought experiment, you mean?”

“Well, from outer space we are just this slime on the surface of the earth. And to, say, an atom, we are these irrelevant giants.”

We held hands between the chairs, watching the lake turn different shades of violet and black. After a while, without looking at me, Jack said:

“Maddy?”

“What.”

“Do they ever tell you exactly what’s going on?”

“With my treatments, you mean?”

“Don’t talk about it if you don’t want to.”

“We have to be optimistic,” I said, copying my mother.