“You of all people should realize that’s not the waitress’s fault.” For years, all through our twenties, Vi had worked at restaurants. But she was still regarding me skeptically as I set down my credit card, and I added, “It’s rude not to tip extra when you bring little kids.” We were at a conversational crossroads. Either we could stand, I could gather the mess of belongings that accompanied me wherever I went—once I had been so organized that I kept my spice rack alphabetized, and now I left hats and bibs and sippy cups in my wake, baggies of Cheerios, my own wallet and sunglasses—and the four of us could head out to the parking lot and then go on to drop Vi at her house, all amicably. Or I could express a sentiment that wasn’t Vi, in her way, asking me to share?

“I believe in tipping well for great service,” Vi was saying. “This girl was phoning it in.”

I said, “If you feel equally attracted to men and women, why not date men? Isn’t it just easier? I mean, I wish it weren’t true, but—” I glanced at my daughter right as she pulled a ficus leaf off the plant and extended her tongue toward it. I had assumed the plant was fake and, therefore, durable, and I called out, “No mouth, Rosie. Come over here.” When I looked back at Vi, I couldn’t remember what I’d wanted to say next. Hadn’t I had another point? And Vi was sneering in a way that made me wish, already, that I’d simply let the moment pass.

“Easier?” Her voice was filled with contempt. “It’s just easier to be straight? As in, what, less embarrassing to my uptight sister?”

“That’s not what I said.”

“Don’t you think it would be easier if black people hadn’t demanded to ride in the front of the bus like white people? Or go to the same schools? That was so awkward when that happened!” This seemed to be an indirect reference to my friend Hank, but I ignored it.

“I don’t have a problem with gay people,” I said, and my cheeks were aflame, which I’d have known, even if I hadn’t been able to feel their heat, by the fact that Vi’s were, too. We would always be identical twins, even though we were no longer, in most ways, identical.

“Where’s Rosie’s baloney?” Rosie said. She had returned from the ficus plant—thank goodness—and was standing next to me.

“It’s at home,” I said. “We didn’t bring it.” The baloney was a piece from a lunch-themed puzzle, a life-sized pink wooden circle on a yellow wooden square, that Rosie had recently become inexplicably attached to. I said to Vi, “Don’t make me out to be homophobic. It’s a statement of fact that life is simpler—it is, Vi—don’t look at me like that. It’s not like two women can get married in Missouri, and there’s a lot of financial stuff that goes along with that, or visiting each other in the hospital. Or having kids—for gay couples, that’s complicated and it’s expensive, too.”

“Having kids period is complicated!” Vi’s anger had taken on an explosive quality, and I felt people at nearby tables looking toward us. “And this whole making-life-simpler bullshit?” she continued. While I flinched at the swear word in front of Rosie, it didn’t seem intentional—there was no question that Vi sometimes liked to provoke me, but it appeared she was swept up in the moment. “Children are nothing but a problem people create and then congratulate themselves on solving. Look at you and Jeremy, for Christ’s sake. ‘Oh, we can’t leave the house because it’s Rosie’s naptime, we can’t be out past five forty-five p.m.’ or whenever the fuck it is—” I was pretty sure Rosie had only a vague notion of what these obscenities, or anything else Vi was saying, meant, but I could sense her watching rapt from beside me, no doubt even more enthralled because she’d heard her own name. “Or, ‘She can’t wear that sunscreen because it has parabens in it’—I mean, seriously, can you even tell me what a paraben is?—and ‘She can’t eat raw carrots because she might choke,’ and on and on and on. But who asked you to have children? Do you think you’re providing some service to the world? You got pregnant because you wanted to—which, okay, that’s your right, but then other people can’t do what they want to because it’s too complicated?”

“Fine,” I said. “Forget I said anything.” “Don’t be a pussy.”

I glared at her. “Don’t call me names.”

“Well, it seems awfully convenient that you get to speak your mind and then close down the discussion.”

“I need to go home for their naps,” I said, and there was a split second in which Vi and I looked at each other and almost laughed. Instead, sourly, she said, “Of course you do.”

In the car, she was silent, and after a couple minutes, Rosie said from the backseat, “Mama wants to sing the Bingo song.”

“I’ll sing it later,” I said.

“Mama wants to sing the Bingo song now,” Rosie said, and when I didn’t respond, she added in a cheerful tone, “When you take off your diaper, it makes Mama very sad.”

Vi snorted unpleasantly. “Why don’t you just toilet train her?” “We’re going to soon.”

Vi said nothing, and loathing for her flared up in me, which was probably just what she wanted. It was one thing for my sister to fail to appreciate the energy I put into our lunches, the sheer choreography of getting a six-month-old and a two-year-old out of the house, into the car, into a restaurant, and back home with no major meltdowns (never in my children’s presence could I have ordered a meal as intricately, messily hands-on as a fajita), but it was another thing entirely for Vi to mock me. And yet, in one final attempt at diplomacy, as I stopped the car on the street outside the small single-story gray house where Vi lived, I said, “For Dad’s birthday, I was thinking—”

“Let’s talk about it later.”

“Fine.” If she thought I was going to plead for forgiveness, she was mistaken, and it wasn’t just because we really did need to get home for Rosie and Owen’s naps. She climbed from the car, and before she shut the door, I said, “By the way?”

A nasty satisfaction rose in me as she turned. She was prepared for me to say, I didn’t mean to be such a jerk in the restaurant. Instead, I said, “Parabens are preservatives.”

Fourteen hours later, at three in the morning, our squabble was what I was stewing over; specifically, I was thinking that the reason I’d made my points so clumsily was that what I really believed was even more offensive than that being straight was easier than being gay. I believed Vi was dating women because she was at her heaviest ever—she’d quit smoking in the spring, and now she had to be sixty pounds overweight—and most lesbians seemed to be more forgiving about appearances than most straight men. I didn’t think I’d object to Vi being gay if I believed she actually was, but something about this development felt false, akin to the way she’d wished, since our adolescence, that she’d been born Jewish, or the way she kept a dream catcher above her kitchen sink. Lying there in the dark next to Jeremy, I wondered what would happen if I were to suggest that she and I do Weight Watchers together; I myself was still carrying ten extra pounds from being pregnant with Owen. Then I thought about how most nights Jeremy and I split a pint of ice cream in front of the TV, how it was pretty much the best part of the day—the whole ritual of relaxation after both children were asleep and before Owen woke up for his ten p.m. nursing— and how it seemed unlikely that half a pint of fudge ripple was part of any diet plan. This was when the bed in which Jeremy and I slept began to shake.

I assumed at first that Jeremy was causing the mattress to move by turning over, except that he wasn’t turning. The rocking continued for perhaps ten seconds, at which point Jeremy abruptly sat up and said, “It’s an earthquake.” But already the rocking seemed to be subsiding.

I sat up, too. “Are you sure?”

“You get Owen and I’ll get Rosie.” Jeremy had turned on the light on his nightstand and was walking out of the room, and as I hurried from bed, adrenaline coursed through me; my heart was beating faster and I felt simultaneously unsteady and purposeful. In his crib, illuminated by a starfish-shaped night-light, Owen was lying on his back as I’d left him an hour earlier, his arms raised palms up on either side of his head, his cheeks big and smooth, his nose tiny. I hesitated just a second before lifting him, and I grabbed one of the eight pacifiers scattered in the crib. As I’d guessed he would, he blinked awake, seeming confused, but made only one mournful cry as I stuck in the pacifier. In the small central hallway that connected the house’s three bedrooms, we almost collided with Jeremy and Rosie, Rosie’s legs wrapped around Jeremy’s torso, her arms dangling limply over his shoulders, her face half-obscured by tangled hair. Her eyes were open, I saw, but barely.

“Do we go to the basement?” I said to Jeremy. The shaking had definitely stopped.

“That’s tornadoes.”

“What is it for earthquakes?” In retrospect, it’s hard to believe I needed to ask, hard to believe I had reached the age of thirty-four and given birth to two children without bothering to learn such basic information.

Jeremy said, “In theory, you get under a table, but staying in bed is okay, too.”

“Really?” We looked at each other, my husband sweet and serious in his gray T-shirt and blue-striped boxer shorts, our daughter draped across him.

“You want me to check?” He meant by looking online from his phone, which he kept beside the bed at night.

“We shouldn’t call Courtney, should we?” I said. “They must have felt it if we did.” Courtney Wheeling was Jeremy’s colleague at Washington University—his area of study was aquatic chemistry, hers was seismology and plate tectonics—and she and her husband, Hank, lived down the street and were our best friends.

“It doesn’t seem necessary,” Jeremy said. “I’ll look at FEMA’s website, but I think the best thing is for all of us to go back to bed.”

I nodded my chin toward Rosie. “Keeping them with us or in their own rooms?”

Rosie’s head popped up. “Rosie sleeps with Mama!” A rule of thumb with Rosie was that whether I did or didn’t think she was following the conversation, I was always wrong.

“Keeping them,” Jeremy said. “In case of aftershocks.”

In our room, I climbed into bed holding Owen, shifting him so he was nestled in my right arm while Jeremy helped Rosie settle on my other side. I wasn’t sure whether to be alarmed or pleasantly surprised that Jeremy was all right with having the kids sleep with us. In general, he was the one who resisted bringing them into our bed; he’d read the same books in Rosie’s infancy that I had, half of which argued that sharing a bed with your kids was the most nurturing thing you could do and the other half of which warned that doing so would result in your smothering them either figuratively or literally. But I liked when they were close by—whether or not it really was safer, at some primitive level it felt like it had to be—and the thought of them sleeping alone in their cribs sometimes pinched at my heart. Besides, I could never resist their miniature limbs and soft skin.

Rosie curled toward me then, tapping my arm, and I turned— awkwardly, because of how I was holding Owen—to look at her. She said, “Rosie wants a banana.”

“In the morning, sweetheart.”

Jeremy had gone to the window that faced the street, and he parted the curtains. “Everyone’s lights are on,” he said.

“A monkey eats a banana peel,” Rosie declared. “But not people.” “That’s true,” I said. “It would make us sick.”

Jeremy was typing on his phone. After a minute, he said, “There’s nothing about it online yet.” He looked up. “How’s he doing?”

“He’s more asleep than awake, but will you get an extra binky just in case?” Surely this was evidence of the insularity of our lives: that unless otherwise specified, whenever Jeremy or I said he, we meant our son, and whenever we said she, we meant our daughter. On a regular basis, we sent each other texts consisting in their entirety of one letter and one punctuation mark: R? for How’s Rosie doing? and O? for How’s Owen? And surely it was this insularity that so irritated Vi, whereas to me, the fact that my life was suburban and conventional was a victory.

Jeremy returned from Owen’s room with a second pacifier, handed it to me, and lay down before turning off the light on his nightstand. Then— I whispered, because whispering seemed more appropriate in the dark— I said, “So if there are aftershocks, we just stay put?”

“And keep away from windows. That’s pretty much all I could find on the FEMA site.”

“Thanks for checking.” Over Owen’s head, I reached out to rub Jeremy’s shoulder.

I felt them falling asleep one by one then, my son, my daughter, and my husband. Awake alone, I experienced a gratitude for my life and our family, the four of us together, accounted for and okay. In contrast to the agitation I’d  been gripped by before the earthquake, I was filled with calmness, a sense that we’d passed safely through a minor scare—like when you speed up too fast in slow highway traffic and almost hit the car in front of you but then you don’t. The argument with Vi, inflated prior to the quake, shrank to its true size; it was insignificant. My sister and I had spent three decades bickering and making up.

But now that several years have passed, it pains me to remember this night because I was wrong. Although we were safe in that moment, we hadn’t passed through anything. Nothing was concluding, nothing was finished; everything was just beginning. And though my powers weren’t what they once had been, though I no longer considered myself truly psychic, I still should have been able to anticipate what would happen next.

From the book “SISTERLAND” by Curtis Sittenfeld. Copyright © 2013 by Curtis Sittenfeld. Reprinted by arrangement with Random House, an imprint of The Random House Publishing Group, a division of Random House, Inc.  All rights reserved.