And Tansy wasn’t here.

Adam looked at me, frown deepening into something sharp. “That’s what Tansy does,” he said. “She doesn’t think much before she helps other people. Or hurts them, sometimes. She says it’s because of the parts in her brain that aren’t functioning optimally. I think she’s trying to get hurt badly enough that Mom will transplant her into a new host, but I don’t want that to happen. She wouldn’t be Tansy anymore if that happened. She’d be someone else.”

I blinked. “Wait—that’s a thing that Dr. Cale can do? She could just scoop you out of the body you’re in and put you into a different one?”

“Sort of,” said Adam. “She says it becomes a question of nature and nurture, because memories don’t carry over, just core personality and epigenetic data, and—wait. Are you trying to distract me? Where’s Tansy, Sal? Why didn’t she come back here with you?”

I took a deep breath, which barely warmed the ball of ice sitting in my stomach, and said, “She stayed behind, Adam. There were a bunch of sleepwalkers—more than I’ve ever seen in one place—and they were going to hurt me, and Nathan. So Tansy stayed behind to fight them. She bought us the time that we needed to get away.” She’d gone down under a wall of bodies, all of them biting and clawing at her like the fact that she was only developmentally one step removed from the sleepwalkers didn’t matter—and maybe it didn’t. I didn’t feel any kinship to them, and never had, but with every minute that passed, I was feeling more as if she and Adam were, and had always been, family.

I really should have seen it sooner. Neither he nor Tansy had ever upset me the way the sleepwalkers did, even though they should have. Especially Tansy, whose methods of communication were brusque at best, and dangerous at worst. I’d already known on some level that we were the same, and it was easier to be forgiving of family. That’s what family was for. I didn’t know how I knew that. I probably shouldn’t have, given my experiences with Sally’s family. But I knew.

“Why didn’t you stay and help her?” asked Adam blankly.

“I couldn’t. I don’t know how to fight, and the information I had… I had the information Dr. Cale needed. If I’d stayed to help Tansy, the information would have been lost, and then Dr. Cale wouldn’t have been able to continue her work.” The knot of ice in my stomach seemed to be loosening a little.

“Oh.” Adam mulled this over for a few moments, looking even younger while he did. Maybe that was one of the functions of the tapeworm-to-human interface. I had perceived a certain childishness about Tansy, and my parents—Sally’s parents—used to comment on the fact that I looked young and lost when I was thinking. It was one more thing I didn’t share with their original daughter, who had never been much for stopping to think about things, and certainly wouldn’t have looked lost while she was doing it.

It hurt a little to realize that I didn’t entirely think of them as my parents anymore; not the same way I had only a few weeks before. They would always be a part of who I was, but I no longer felt the need to try to make them love me, and that felt like the sort of bond that should have taken longer to break. Maybe it was different when the bond had never fully formed. They’d always be important to me, but they hadn’t made me.

“Well, I guess she’ll tell me what happened when she gets back,” said Adam finally, and walked over to sit down on the edge of the cot, looking at me with wide, guileless eyes. “Are you feeling better? You sure do faint a lot.”

“I get startled a lot,” I said, smiling despite myself. “What about you? You’ve never fainted? Not even once?”

“A few times, when I first woke up,” he said. “Mom says it’s because some of the blood vessels feeding into my brain were compromised during my surgery, and they needed time to recover.”

I wondered absently if I might be dealing with something similar. It didn’t seem likely. Any weak blood vessels would have been found and fixed by SymboGen years ago. I was just dealing with plain, old-fashioned shock, and that was actually a little reassuring: at least something about me was plain and old-fashioned.

“Oh,” I said. I took a deep breath. “Adam, can I ask you something sort of personal?”

Adam sat up a little straighter, going still. “Yes,” he said, after a moment’s hesitation. “You can ask me anything.”

“I…” I stopped. I didn’t know how to frame the question that came next. I didn’t even know how to start. “Did you know I wasn’t human?” seemed too accusatory, and “Have you noticed anything strange about me?” felt almost, well, coy. I finally settled for “Do you like being you?”

A wide smile spread across Adam’s face, tight-lipped, so that his teeth were concealed. I realized with a start that he’d never shown his teeth when he smiled at me. That was a mammalian gesture, and the part of him—the part of me—that drove those reactions wasn’t mammalian. “I love it,” he said. “I have hands, and feet, and fingers, and eyes, and it’s wonderful, Sal, it’s just wonderful. There’s so much world. I could live a hundred years and never see all of the world that there is to see. Mom gave it to me. You know? Mom made it so I could walk and dance and sing and run bacteriological cultures for her and it’s just wonderful. You know that, right? That life is wonderful.” His smile faded, replaced by a look of grave concern.