A real friend isn't capable of feeling sorry for you.

"I'm not your friend," I say, yanking the curtain back into place. "I'm your sister." And doing a damn lousy job at that, I think. I push my face into the shower spray, so that she cannot tell I'm crying, too.

Suddenly, the curtain whips aside, leaving me totally bare. "That's what I wanted to talk about," Kate says. "If you don't want to be my sister anymore, that's one thing. But I don't think I could stand to lose you as a friend."

She pulls the curtain back into place, and the steam rises around me. A moment later I hear the door open and close, and the knife-slice of cold air that comes on its heels.

I can't stand the thought of losing her, either.

That night, once Kate falls asleep, I crawl out of my bed and stand beside hers. When I hold my palm up under her nose to see if she's breathing, a mouthful of air presses against my hand. I could push down, now, over that nose and mouth, hold her when she fights. How would that really be any different than what I am already doing?

The sound of footsteps in the hallway has me diving underneath the cave of my covers. I turn onto my side, away from the door, just in case my eyelids are still flickering by the time my parents enter the room. "I can't believe this," my mother whispers. "I just can't believe she's done this."

My father is so quiet that I wonder if maybe I have been mistaken, if maybe he isn't here at all.

"This is Jesse, all over again," my mother adds. "She's doing it for the attention." I can feel her looking down at me, like I'm some kind of creature she's never seen before. "Maybe we need to take her some-where, alone. Go to a movie, or shopping, so she doesn't feel left out. Make her see that she doesn't have to do something crazy to get us to notice her. What do you think?"

My father takes his time answering. "Well," he says quietly, "maybe this isn't crazy."

You know how silence can push in at your eardrums in the dark, make you deaf? That's what happens, so that I almost miss my mother's answer. "For God's sake, Brian… whose side are you on?"

And my father: "Who said there were sides?"

But even I could answer that for him. There are always sides. There is always a winner, and a loser. For every person who gets, there's someone who must give.

A few seconds later, the door closes, and the hall light that has been dancing on the ceiling disappears. Blinking, I roll onto my back—and find my mother still standing beside my bed. "I thought you were gone," I whisper.

She sits down on the foot of my bed and I inch away. But she puts her hand on my calf before I move too far. "What else do you think, Anna?"

My stomach squeezes tight. "I think… I think you must hate me."

Even in the dark, I can see the shine of her eyes. "Oh, Anna," my mother sighs, "how can you not know how much I love you?"

She holds out her arms and I crawl into them, as if I'm small again and I fit there. I press my face hard into her shoulder. What I want, more than anything, is to turn back time a little. To become the kid I used to be, who believed whatever my mother said was one hundred percent true and right without looking hard enough to see the hairline cracks.

My mother holds me tighter. "We'll talk to the judge and explain it. We can fix this," she says. "We can fix everything." And because those words are really all I've ever wanted to hear, I nod.

THERE IS AN UNEXPECTED COMFORT to being at the oncology wing of the hospital, a sense that I am a member of the club. From the kindhearted parking attendant who asks us if it's our first time, to the legions of children with pink emesis basins tucked beneath their arms like teddy bears—these people have all been here before us, and there's safety in numbers.

We take the elevator to the third floor, to the office of Dr. Harrison Chance. His name alone has put me off. Why not Dr. Victor? "He's late," I say to Brian, as I check my watch for the twentieth time. A spider plant languishes, brown, on a windowsill. I hope he is better with people.

To amuse Kate, who is starting to lose it, I inflate a rubber glove and knot it into a coxcomb balloon. On the glove dispenser near the sink is a prominent sign, warning parents not to do this very thing. We bat it back and forth, playing volleyball, until Dr. Chance himself comes in without a single apology for his delay.

"Mr. and Mrs. Fitzgerald." He is tall and rail-thin, with snapping blue eyes magnified by thick glasses, and a tightly set mouth. He catches Kate's makeshift balloon in one hand and frowns at it. "Well, I can see there's already a problem."

Brian and I exchange a glance. Is this coldhearted man the one who will lead us through this war, our general, our white knight? Before we can even backpedal with explanations, Dr. Chance takes a Sharpie marker and draws a face on the latex, complete with a set of wire-rimmed glasses to match his own. "There," he says, and with a smile that changes him, he hands it back to Kate.

I only see my sister Suzanne once or twice a year. She lives less than an hour and several thousand philosophical convictions away.

As far as I can tell, Suzanne gets paid a lot of money to boss people around. Which means, theoretically, that she did her career training with me. Our father died while mowing the lawn on his forty-ninth birthday; our mother never quite sewed herself together in the aftermath. Suzanne, ten years my senior, took up the slack. She made sure I did my homework and filled out law school applications and dreamed big. She was smart and beautiful and always knew what to say at any given moment. She could take any catastrophe and find the logical antidote to cure it, which is what made her such a success at her job. She was just as comfortable in a boardroom as she was jogging along the Charles. She made it all look easy. Who wouldn't want a role model like that?

My first strike was marrying a guy without a college degree. My second and third were getting pregnant. I suppose that when I didn't go on to become the next Gloria Allred, she was justified in counting me a failure. And I suppose that until now, I was justified in thinking that I wasn't one.

Don't get me wrong, she loves her niece and nephew. She sends them carvings from Africa, shells from Bali, chocolates from Switzerland. Jesse wants a glass office like hers when he grows up. "We can't all be Aunt Zanne," I tell him, when what I mean is that I can't be her.

I don't remember which of us stopped returning phone calls first, but it was easier that way. There's nothing worse than silence, strung like heavy beads on too delicate a conversation. So it takes me a full week before I pick up the phone. I dial direct. "Suzanne Crofton's line," a man says.

"Yes." I hesitate. "Is she available?"

"She's in a meeting."

"Please…" I take a deep breath. "Please tell her it's her sister calling."

A moment later that smooth, cool voice falls into my ear. "Sara. It's been a while."

She is the person I ran to when I got my period; the one who helped me knit back together my first broken heart; the hand I would reach for in the middle of the night when I could no longer remember which side our father parted his hair on, or what it sounded like when our mother laughed. No matter what she is now, before all that, she was my built-in best friend. "Zanne?" I say. "How are you?"

Thirty-six hours after Kate is officially diagnosed with APL, Brian and I are given an opportunity to ask questions. Kate messes with glitter glue with a child-life specialist while we meet with a team of doctors, nurses, and psychiatrists. The nurses, I have already learned, are the ones who give us the answers we're desperate for. Unlike the doctors, who fidget like they need to be somewhere else, the nurses patiently answer us as if we are the first set of parents to ever have this kind of meeting with them, instead of the thousandth. "The thing about leukemia," one nurse explains, "is that we haven't even inserted a needle for the first treatment when we're already thinking three treatments down the line. This particular illness carries a pretty poor prognosis, so we need to be thinking ahead to what happens next. What makes APL a little trickier is that it's a chemoresistant disease."