This morning around six a young birch tree I planted last fall snapped in half with such a resolute crack that it woke us all up. I sat bolt upright in bed and the cats did too, riveted in the direction of the window, ears cocked. The sound was hard to figure out. I thought maybe a Canada goose had landed on the roof.

There was no noise but the rain. Sid leapt off the bed and onto the windowsill, followed by Angus, Red Jack, and Gracie, and I finally got up and looked out, seeing immediately that the birch had fallen because it's right next to the one that broke last week which I hadn't dug out yet and carted away.

I pay attention to sound. My mother and her father both began to go deaf in their 40's. Grandpa wore hearing aids and looked thoughtful when you asked him a question, as though he were carefully considering the answer. Then he'd say something totally off the point. Mom went through 20 years of innovation in hearing aids before she learned American Sign. Chemo knocked the last sounds from her ears, but she could read lips pretty well by then, especially those of her children. I've tried this in restaurants and watching foreign movies and I can't do it at all, it's incredibly hard.

My siblings and I are constantly making jokes about deafness because we're terrified it will happen to us, too — a day doesn't go by when I don't notice some kind of sound: rain on the roof, birdsong, my engine idling at a stop sign, a weekend chain saw. So when the birch snapped and woke me up, one of the 200 simultaneous swirling thoughts in my head, right after "Am I alive?" was, "Hey! I can still hear!"

I planted those two birches as memorials to my mother and my great-aunt Net, who died within a year of each other. They'd both spent a lot of time in Vermont and loved the white bark and whispering, heart-shaped leaves. It's awful to plant trees in memory of people you love and then have them not thrive. It makes me feel like a bad daughter, as though I didn't love them enough. No matter that young trees are known to break like this when sap rises too fast.

When my mother called to tell me she had cancer, there was a TTY operator on the line with us who typed my responses so they appeared on a little screen on Mom's phone and she could read them. It was a pretty tough conversation, as you might imagine, and the operator kept having to type in "sound of crying."

I hope I never lose my hearing, but in case I do, I've been collecting every noise I want to remember. Including Mozart and windchimes and the ocean during a storm. Including cats purring in my arms. Including that operator's "I'm so sorry," after my mother hung up. And the crack of a tree breaking in the early morning, and the swish of branches brushing down the side of a house as they fall.