The Baby Monitor Picks Up a Lullaby From Upstairs

New parents live by the baby monitor, and ours was a good one, digital, paired to the nursery unit, private frequency, all the reassurance modern anxiety can buy. For the first weeks it did its job: our son's breathing, his snuffles, the occasional cry that sent one of us stumbling up the stairs. Then it started picking up the singing.

A woman's voice, soft, singing a lullaby. Not our son — obviously — and not me; I'd be beside the monitor's parent unit, downstairs, when it came through, and not my husband, who cannot hold a tune to save his life and has the range of a gate hinge. A gentle female voice, humming and singing a slow old lullaby, coming through the monitor that was tuned, privately and digitally, to our son's nursery, in a house that contained, at those moments, only me downstairs, my husband beside me, and our sleeping son upstairs.

I did the modern-parent diligence. Digital monitors on private frequencies aren't supposed to pick up the neighbours — that was the whole selling point, the reason we'd spent more than we should have. I checked for interference, changed the channel, factory-reset it. The singing continued, most nights, always the same slow lullaby, always the same soft voice, always from the nursery unit, where our son slept alone. I went up, more than once, mid-song, monitor in hand, and stood in the nursery doorway, and the room was quiet, my son breathing softly in his cot, no voice, no singing — and yet the monitor in my hand, receiving from the unit three feet away, carried the woman's lullaby into my ear while the room in front of me was silent. The song was in the transmission. It was not in the room.

Here is the part that made me stop trying to fix it and start, instead, to listen. Our son, who was a difficult, colicky, wakeful baby who fought sleep with his whole small body, slept through the singing. More than slept — settled by it. On the nights the lullaby came, he went down easily and stayed down, peaceful, as though soothed by a voice I couldn't see and he apparently could hear, or feel, or knew. The nights it didn't come were the hard ones. I started, God help me, to hope for it.

I asked my husband's mother, eventually, about the house — it had been in his family, passed down; his grandmother had raised her children in it, and her mother before her. I described the lullaby as best I could hum it, and my mother-in-law went quiet, and then sang it back to me, correctly, the melody and the old dialect words — her own mother's lullaby, she said, the one sung to every baby in that house for four generations, the one she'd sung to my husband, the one HER mother had sung to her, in that nursery, in that house. A great-great-grandmother's lullaby, still being sung, in that room, to the newest baby of the line, on a private digital frequency she could have no way of knowing existed, soothing a colicky boy to sleep with four generations of the same soft voice.

We kept the monitor. Of course we kept the monitor. Our son is three now and long out of the nursery, and the singing stopped when he did, the voice apparently satisfied that this one, too, had been sung safely through the wakeful nights. My mother-in-law sings him the lullaby still, in person, the ordinary way. But for two years someone who loved that house and its babies enough to outlast four generations sang my difficult son to sleep through a monitor, in a voice I never placed until his great-great-grandmother's song came out of my mother-in-law's mouth, and I have never been so unafraid of a ghost in my life.