“Wow. Look at that,” Dad says. He picks his left hand off the steering wheel and points. Twenty yards ahead, in a white Mercedes Benz, we see the silhouettes of a driver and a woman with a lot of fluffy hair. They are kissing. Really kissing. I’m positive my health teacher would see this and call it heavy petting. The more the driver absorbs himself in the kiss the further the car veers to the right. The rumble of the warning strip makes him look up and pull the wheel to the left.

“Thank goodness there aren’t too many people on the road this early,” Mom says. “Keep your distance, Kevin.”

I tighten my ponytail and sit up to get a better look, relieved to focus on something else besides being wedged between my parents’ friends in the backseat of my father’s Tercel. Because it’s a holy day of obligation, and because on these days my parents always force me to go to mass before school, they woke me up at five o’clock in the morning so that we could drive Mr. and Mrs. Green to Logan and then get to church on time. Every holy day makes me hate my parents a little bit more.

“Is he drunk?” I ask.

“Drunk on love, maybe,” Mr. Green says. He laughs through his nose, which instinctually makes me check my sleeves and skirt. I’m in the clear. “Awful amorous for this time of day,” he says.

I spot my father looking at Mr. Green in the rearview mirror. I can tell from Dad’s expression that he is happy to see his friend smiling—this friend from his military days who has come up north from Louisiana with his wife to visit us, to get away from his home, where everything reminds him of the daughter he lost two months ago to suicide. Mom told me she took some pills before going to bed. Her name was Suzanne; everyone called her Suzie. She was three years older than me. I only met Suzie twice; once, when I was a baby. We have a photograph of us propped on a couch; we are holding hands. When Mom showed this photograph to the Greens, it made everyone cry.

“She was molested as a young child,” Mom told me after we heard the news, as if this would explain everything. We were in the kitchen, and Mom was chopping green peppers. I must have seemed confused because she stopped and asked, “Sweetheart, you know what ‘molested’ means, right?”

“I’m not stupid, Mom,” I said. I could tell by the restraint in her voice and by the way she’d shifted her attention back to the vegetables, that her end of the conversation was over, bases covered. But I had questions.

“Who did it?” I asked.

Mom kept chopping. “I only know that it was someone from their neighborhood.”

It was not lost on me that we used to live in that same neighborhood, that it could as easily have been me. “Remember the last time we saw her?” I said. I moved closer to my mother. I felt a desire to bury my head in her shoulder, even if I couldn’t admit as much, and even if my mother did not offer it. “I don’t understand,” I said. “She didn’t seem unhappy to me.” Then something about my last conversation with Suzie clicked in my mind.

Mr. Green laughs again, and I can see that Dad wants to get as much mileage out of this moment of levity as he can. He dares to accelerate a little. “Remember when we used to kiss like that, honey?” Dad says.

“Gross,” I say. His behavior is so often humiliating.

Mom puts her hand on the dashboard. “Please remember that your daughter is in the car, Kevin.” Her voice is staccato. “And please slow down.”

He falls behind. “Don’t worry,” Dad says. “Next exit is ours.”

I notice that the Mercedes has its blinker on, and I wonder if they’re going to the airport, too, if these two people are so in love that they can barely stand to say goodbye to one another. That’s the kind of love I want.

I turn to look at Mrs. Green. She has been quiet the entire weekend, just as she is now. Her sadness makes me uncomfortable. After watching her for the past few days, it seems like she wishes she’d been the one to swallow those pills, but I want to tell her that Suzie wouldn’t want that. I very badly want to tell her what Suzie told me when we went to visit them down in Louisiana six months ago—I think it might be of some comfort—but for some reason, I can’t. I’ve barely said anything to Mrs. Green all weekend long. With her thumb, she rolls her wedding ring around and around the deep groove in her pudgy finger. I follow her gaze out the left window and spot a pair of sneakers slung on phone lines, and a lime-green triple-decker with black shutters, its front light on.

Then, as we pull off the exit, I notice that the woman’s head has disappeared. The man is now driving in a perfectly straight line.

“Oh, geez,” Mr. Green says. He is trying to stifle nervous laughter. Instead, he trembles so violently that he makes me shake, and through me, Mrs. Green as well. We learned about this—how energy is transferred—in physics class.

Sharply, Mom says, “Kevin,” and my father immediately applies the brake. Mom turns and looks with concern at Mrs. Green and then at me.

I ask my father to turn on the radio, and he is happy for the distraction. “Oldies 103 okay with everyone?”

“Fine with me,” I say. In situations like this it’s always easier on them—and me—to pretend I have no idea what’s going on.

But I do know. Even if I had been one of the last holdouts in my group of friends, I had finally done with my boyfriend, Bobby, what I’m pretty sure that woman is doing with the driver. Bobby’s persistence about it wore me down. I did it, even though I didn’t like it.

Dad has put some distance between the Mercedes and us, but now we’ve stopped at a red light, directly behind them. Mr. Green starts fidgeting, patting his knees. Suddenly, the woman’s head pops back up, but the driver quickly reaches his free hand to the back of her head and pulls it toward him. With force. The woman’s head kicks back, but he uses that momentum to pull her back down. The rule that says every action has an equal, opposite reaction pops into my head. How strange, I think, that this situation keeps reminding me of something as boring as physics class. My physics teacher likes to use examples from everyday life, but not this example, not now. I try to remember if Bobby put his hand on the back of my head, I try to remember if he pushed, I try to remember if anyone was around the parking lot that night, if anyone could have possibly been a witness.

Seconds later the woman’s head reappears. This time the man grabs a handful of her hair and pulls her down again.

Our car is silent. Mom’s hand moves from the dashboard to her mouth. The other one goes to Dad’s arm. The light turns green, and as we descend into the airport tunnel, the radio goes static.

Then, at the top of her lungs, Mrs. Green shrieks, “For God’s sake, do something!” She seems to have the authority in the car, because everyone begins to react at once. Mr. Green reaches behind me to rub Mrs. Green’s shoulder. I lean forward to get out of the way. Mom writes the license plate number on her hand. Dad lays on the horn. The fluffy-haired lady sits up quickly and moves to the far right of the car.

“Speed up,” Mrs. Green says. “I want to speak to her.”

Dad pulls into the right lane and steps on it. Mrs. Green unrolls her window, and the car fills with the thick underground smell of exhaust. Mr. Green grabs the brim of his new Red Sox cap. Dad’s hairpiece flutters. The wind sweeps a piece of paper off the dashboard and into the backseat. It’s an advertisement for a new television set. “Act now!” it says, and I make a quick wish that this means Mom is going to buy me a television for my fifteenth birthday.

Now we are even with the Mercedes. The man is wearing a business suit. I can see his mouth moving, probably telling the woman to look straight ahead, to act as if nothing happened, to wipe things off, to clean herself up. I hope he has a bath towel or something to help her with this, something other than the shirt she has to wear for the rest of the day. I begin to feel bad for them. They must be embarrassed.

Mrs. Green waves her cell phone out the window and yells, “Do you want us to call the police?” The woman is wearing a crisp white blouse, and she is shielding her eyes from us with her hand. “We can help,” Mrs. Green says desperately.

The woman tucks a piece of her hair behind her ear. She turns to us, her eyes pinched with anger. Her skin, under the tunnel’s fluorescent lighting, matches the dingy walls; the word “sallow,” a vocab word, comes to mind. She opens her window and yells, “Mind your own goddamn business!” Then the car takes off and speeds ahead of us. Dad’s Tercel is no match for the Mercedes.

“Should we call anyway?” Mom says, showing that she has the license plate number. My mother’s eyes are bright, alive.

“What’s the use?” Mrs. Green says. “What’s the use?” She says it again and again, her voice rising, sounding a little more crazed each time. “A mother does not raise her daughter for this!” I wonder if Mrs. Green is losing her mind, if this is what happens when a mother loses her child. She begins to cry, and I can feel it deep in my stomach.

I think again of the last time I saw Suzie. We’d gone to visit the Greens for a reunion with all my parents’ friends from the military base. That first night had been awkward—me, in my pajamas, upright on one double bed flipping through a magazine; Suzie, sprawled on the other. I complimented her on her purple comforters. She told me she liked dark colors because her parents hated them. I thought this was funny. I said, “Yeah, I hate my parents, too.”

“But that’s not what I said,” she responded quickly. “I hate what they love, but I don’t hate them. I couldn’t hate them. They’re the only ones who know everything about me and still love me.”

I didn’t know how to respond to that. When it came to my parents, I wasn’t comfortable talking about love. I believed that I did hate them, or at least disliked them very much. So, I asked her if she had a boyfriend.

“No, not right now,” she said. “You must, or you wouldn’t be asking.” She sat up and looked at me, her cleavage impressively bursting from her tank top. I was struck both by how much more mature she seemed than me, and also by how, in spite of this, she seemed genuinely interested, and kind.

“Well, yeah, sort of,” I said. At the time, Bobby and I had only just started going out, so I told her everything I knew.

“Be careful,” she said and clicked off her bedside lamp.

“Of what?” I asked. I took her lead, closed my magazine, and turned off my light.

A galaxy of neon star stickers illuminated above us. “You give in once, you’ll give in every time.”

I think of this conversation, and I want to tell Mrs. Green that she shouldn’t worry about how she raised her daughter. Suzie had been kind to me, which is more than I can say for half my friends. I want to tell Mrs. Green that I miss Suzie too.

Now, Mr. Green is leaning over me, rubbing Mrs. Green’s back, crushing me with his weight. I manage to unbuckle my seatbelt and scoot forward. I thumb my initials into the fabric of my dad''s seatback and wipe it clean. Then I rest my head near my mom and close my eyes. A song by the Temptations tries to materialize through the static—sweet darlin’, please don’t leave—but then it fades into white noise. I can hear the low hum of the cars underground. My mother rests her hand on mine. I refrain from pulling it away. I know now is not the time to make a scene.

I think again of the man and the woman in that car. The thought that someone might have seen me and Bobby; that, to an outsider, we might have looked like that, has started to make me feel sick. Because now that I think of it, he did, yes, he did press his fingertips through my hair and onto my scalp; he did position me, just so; he did push, and when he came, I drew back, not knowing what to do, and he pulled me to him and hugged me tighter and more tenderly than ever before. I remember feeling very close to him, and I wonder now if this was the kind of thing Suzie had been warning me against.

I feel pressure in my chest. I inhale quickly and hold my breath. My mother hears. “I’m sorry you had to see that, Gretchen,” she says.

The radio starts again full blast. I open my eyes as we emerge from the tunnel, and I see that the hand holding mine is not my mother’s, but Mrs. Green’s. I turn to her. “She loved you,” I say. “She told me.” Mrs. Green squeezes my hand. “I know,” she says. We remain quiet until we drop off the Greens with hugs and tears and promises for prayers. Then we turn around and head north with plenty of time to get to mass.