The second discrepancy arrived three weeks later, and this time Thomas caught it himself, before Victoria had to point toward the fear that had been quietly growing between them since the lake trip his mother remembered and he did not.
Your father's still going on about the Wilsons selling their place next door, the letter read, ordinary and warm as always. Forty years in that house, and now it's some young couple with two kids and a dog that won't stop barking at three in the morning. I miss the quiet, though I suppose that's just what happens when a neighborhood gets younger around you.
Thomas read it twice, and then a third time, the cold dread settling into him with a familiarity that had, if anything, grown worse for being expected this time rather than sudden.
He did not remember the Wilsons. He did not remember, try as he might, any neighbors on either side of his parents' house at all — a blank, smooth absence exactly like the lake trip, exactly like a hole cut cleanly out of a memory that should have been there.
He found Victoria at the tally-bench, and didn't need to explain before she read the trouble plainly in his face.
"Another one," she said.
"The neighbors. My parents' neighbors, of forty years, apparently, and I can't summon a single detail about them. Not a face, not a name until she wrote it, nothing." Thomas sat heavily across from her, the Codex's newest quire — the one he'd begun keeping specifically for these small, growing wrongnesses — already open on the bench between them. "Two in three weeks. If this keeps happening at the same pace, Victoria, I don't know what it means for the whole shape of what I'm losing."
Victoria was quiet a long moment, turning the fear over with the same careful precision she brought to every crisis, though Thomas could see, in the particular stillness of her hands, how much this one cost her differently than the others. "I want to ask you something, and I want you to answer honestly, even if the answer frightens you."
"Ask."
"Is it possible," she said slowly, "that these details aren't disappearing from your memory at all? That they're disappearing from hers instead — from the world you left, rather than from the mind you carried out of it? That your mother is writing about a lake trip and a set of neighbors that used to exist, in the version of that world you actually lived, and don't exist any longer in whatever version she's currently living inside?"
The suggestion landed with a weight Thomas hadn't fully braced for, though some part of him understood, hearing it, that it was exactly the fear he'd been circling without quite letting himself name it directly.
"You think the world itself is changing. Not just my memory of it."
"I think the relay warned you of a deviation cascade, and I think a cascade, by its nature, doesn't stay contained to a single small point. I think you told me once that every change you make here weakens the anchor because it 'heavies' the past — your own word for it, from years ago, before either of us fully understood what it meant. I wonder now if heavies was always the more literal word than either of us gave it credit for." Victoria took his hand, her grip steady despite the tremor beneath it. "I wonder if the world you came from isn't simply growing more distant from you, Thomas. I wonder if it's genuinely becoming a different world than the one you left, changed by every ripple your own presence here has sent backward through whatever strange thread still connects the two."
Thomas sat with that a long while, the candle between them burning low, and found no comfort anywhere in the theory, only a colder, more expansive version of the same dread he'd been carrying since the falling number first frightened him properly.
"If that's true," he said finally, "then it isn't only my own ending I should be afraid of. It's the possibility that the world waiting for me, if I ever do go home, isn't the one I left behind at all. That my mother's already living in a slightly different life than the one she was living the day I disappeared from it, and doesn't even know enough to miss the difference."
"I don't know if it's true, Thomas. I only know it's possible, and that possible things frighten me considerably more when they're left unexamined than when they're written down plainly, however little comfort the writing offers." Victoria pulled the Codex quire closer, and together, in the candlelight, they added the lake trip and the Wilsons both to a growing, careful record of every small wrongness Thomas could no longer be certain belonged to his own fading memory, or to a world quietly, irreversibly becoming something other than the one he'd once called home.