Cora became my one constant, the single thing I could depend on to be there and to remain relatively unchanged, day in and day out. At night in our shared room, I’d often have to lie awake listening to her breathing for a long time before I could fall asleep myself.

“Shhh,” I remembered her saying as we stood in our nightgowns in our bedroom. She’d press her ear against the door, and I’d watch her face, cautious, as she listened to my mom moving around downstairs. From what she heard—a lighter clicking open, then shut, cubes rattling in a glass, the phone being picked up or put down—she always gauged whether it was safe for us to venture out to brush our teeth or eat something when my mom had forgotten about dinner. If my mom was sleeping, Cora would hold my hand as we tiptoed past her to the kitchen. There I’d hold an old acrylic tray while she quickly piled it with cereal and milk—or, my favorite, English-muffin pizzas she made in the toaster oven, moving stealthily around the kitchen as my mother’s breath rose and fell in the next room. When things went well, we’d get back upstairs without her stirring. When they didn’t, she’d jerk awake, sitting up with creases on her face, her voice thick as she said, “What are you two doing?”

“It’s okay,” Cora would say. “We’re just getting something to eat.”

Sometimes, if she’d been out deeply enough, this was enough. More often, though, I’d hear the couch springs squeak, her feet hitting the hardwood floor, and it was then that Cora always stopped whatever she was in the midst of—sandwich making, picking through my mom’s purse for lunch money, pushing the wine bottle, open and sweaty, farther back on the counter—and do the one thing I associated with her more than anything else. As my mother approached, annoyed and usually spoiling for a fight, my sister would always step in front of me. Back then, she was at least a head taller, and I remembered this so well, the sudden shift in my perspective, the view going from something scary to something not. Of course, I knew my mother was still coming toward me, but it was always Cora I kept my eyes on: her dark hair, the sharp angles of her shoulder blades, the way, when things were really bad, she’d reach her hand back to find mine, closing her fingers around it. Then she’d just stand there, as my mother appeared, ready to take the brunt of whatever came next, like the bow of a boat crashing right into a huge wave and breaking it into nothing but water.

Because of this, it was Cora who got the bulk of the stinging slaps, the two-hand pushes that sent her stumbling backward, the sudden, rough tugs on the arm that left red twisty welts and, later, bruises in the shape of fingertips. The transgressions were always hard to understand, and therefore even more difficult to avoid: we were up when we shouldn’t have been, we were making too much noise, we provided the wrong answers to questions that seemed to have no right ones. When it was over, my mother would shake her head and leave us, returning to the couch or her bedroom, and I’d always look at Cora, waiting for her to decide what we should do next. More often than not, she’d just leave the room herself, wiping her eyes, and I’d fall in behind her, not talking but sticking very close, feeling safer if she was not just between me and my mom, but between me and the world in general.

Later, I’d develop my own system for dealing with my mom, learning to gauge her mood by the number of glasses or bottles already on the table when I came home, or the inflection in her tone when she said the two syllables that made up my name. I took a few knocks as well, although this became more rare when I hit middle school. But it was always the singing that was the greatest indicator, the one thing that made me hesitate outside a door frame, hanging back from the light. As beautiful as her voice sounded, working its way along the melodies I knew by heart, I knew there was a potential ugliness underneath.

By then, Cora was gone. A great student, she’d spent high school working shifts at Exclamation Taco! for college money and studying nonstop, to better her chances of receiving any one of the several scholarships she’d applied for. My sister was nothing if not driven and had always balanced the chaos that was our lives with a strict personal focus on order and organization. While the rest of the house was constantly dusty and in disarray, Cora’s side of our shared room was neat as a pin, everything folded and in its place. Her books were alphabetized, her shoes lined up in a row, her bed always made, the pillow at a perfect right angle to the wall. Sometimes, sitting on my own bed, I’d look across and be amazed at the contrast: it was like a before-and-after shot, or a reverse mirror image, the best becoming the worst, and back again.

In the end, she received a partial scholarship to the U, the state university one town over, and applied for student loans to cover the rest. During the spring and summer of senior year, after she’d gotten her acceptance, there was a weird shift in the house. I could feel it. My sister, who’d spent most of the last year avoiding my mother entirely— going from school to work to bed and back again—suddenly seemed to loosen up, grow lighter. People came to pick her up on weekend nights, their voices rising up to our open windows as she got into their cars and sped away. Girls with easy, friendly voices called asking for Cora, who’d then take the phone into the bathroom where, even through the door, I could hear her voice sounded different speaking back to them.

Meanwhile my mother grew quieter, not saying anything as Cora brought home boxes to pack for school or cleaned out her side of the room. Instead, she just sat on the side porch during those long summer twilights, smoking cigarettes and staring off into the side yard. We never talked about Cora leaving, but as the day grew closer, that shift in the air was more and more palpable, until it was as if I could see my sister extracting herself from us, twisting loose and breaking free, minute by minute. Sometimes at night, I’d wake up with a start, looking over at her sleeping form across the room and feel reassured only fleetingly, knowing that the day would come soon when there would be nothing there at all.