I think my luck may be finally starting to change, because just before ten, Mom realizes that she got buttermilk instead of heavy cream and says in an irritated voice that she’ll have to go to the store.

“We’ll do it,” Lily and I say together. This is much better than sneaking out yet again.

Mom stares at us suspiciously. “It’s too late,” she says.

“There’s no school tomorrow, Mom,” I argue. “It doesn’t matter if we go out.”

“We just want to help,” Lily adds convincingly. “You’re already doing so much.”

Here are two things you should know about Lily.

1. She is a great liar.

2. She is an even better sister (see #1).

“Since when do you girls do things together?” Mom asks, putting a hand on her hip.

“Honey,” Dad says, looking up from the movie we’d been watching with him on the couch, “don’t look a gift horse in the mouth.”

“Oh, all right,” Mom says. “But drive slow.”

“We will,” Lily replies, chancing a smile at me. “Very, very slow.”

Five minutes later, we’re in the car.

“I still don’t understand why we’re doing this,” Lily says.

“I know,” I reply.

But Gram would understand. She would say that what I’m doing is right. That sometimes the best thing you can do is forget about your own battle for a while and help someone else. Especially someone who is fighting a losing one.

Soon, we pull up in front of a big house with a yawning front lawn of grass that, even in the dark, you can tell is neatly clipped. All the lights are off, but somewhere on the first floor, blue television light splashes out from the windows.

“Just wait here,” I say. “It’ll only take a sec.”

Then I climb out of the car, into the freezing-cold night, clutching the book tightly to my chest. Silently, I walk up to the porch, and I’m just about to set the book down there when the door swings open.

Edie O’Shea stares out at me from her dark house.

“Emma?”

I freeze. This was not part of the plan.

“What are you doing here?”

I look down at Lily’s copy of The World at the End of the Tunnel. At the story I’ve cherished for so long. The one that helped Gram get through her darkest years.

And suddenly I feel very, very stupid.

What am I doing here with this book? Edie is going to think I’m crazy. She’s going to tell everyone at school that I’m stalking her or something.

But then I think again of Gram, and I take a deep breath.

“I just—I was going to leave this for you,” I say, cheeks warm despite the cold.

Edie reaches out a hand for the book. “I’ve heard of this one,” she says, “but I’ve never read it.”