Don’t, I tell him. That would really upset Mom.

My immediate first instinct is to ask him how I am supposed to get to Jess’s if he goes home sick, but then I remember Jess telling me that not everything is about me, and that putting yourself in someone else’s shoes is part of social interactions. (Not literally. I would not fit in Theo’s shoes. He wears a ten and a half, while I wear a twelve.) So I tell Theo to feel better and then I go to the guidance counselor, Mrs. Grenville. We examine the map Jess has given me and decide that I should take Bus H-5 and get off at the third stop. She even draws a route in highlighter pen from the bus stop to the house.

As it turns out, the map is a very good one, even if it’s not drawn to scale. After I get off the bus, I turn right at the fire hydrant and then count six houses on the left. Jess’s new temporary home is an old brick house with ivy growing up the sides. I wonder if she knows that the tendrils of ivy can break apart mortar and brick. I wonder if I should tell her. If someone told me, I would lie in bed at night wondering if the whole house was going to crumble around me.

I am still very nervous when I ring the front doorbell, because I have never seen the inside of this house before and that makes me feel like my bones have gone to jelly.

No one answers, so I go around the back.

I glance down at the snow and make a mental note of what I see, but it isn’t really important because The Door Is Unlocked, and that must mean Jess is expecting me. I feel myself relaxing already: it’s just like her dorm room; I will go in and wait, and when she returns, everything will be back to normal.

There are only two times that Jess has gotten angry with me, and both occurred while I was waiting for her to show up. The first was when I took all her clothes out of her closet and arranged them according to the electromagnetic color spectrum, like mine. The second time was when I sat down at her desk and noticed the calculus problem set she was working on. She’d done half the problems wrong, so I fixed them for her.

Theo is the person who made me understand that the rules of violence are based on threat. If there is an actual problem, there are only two options:

1. Retaliation

2. Confrontation

It’s gotten me into trouble.

I have been sent to the principal’s office for smacking a boy who threw a paper airplane at me during English class. When Theo ruined one of my forensic experiments-in-progress, I went into his bedroom with a pair of scissors and systematically hacked his comic book collection to bits. Once in eighth grade, I found out that a group of kids were making fun of me, and as if someone had flipped an electrical switch inside me, I went into a frantic rage. I huddled in a cubicle in the school library, crafting a hit list of the people I hated and how I would like their lives to end: knife wound in the locker room at gym, bomb in their locker, cyanide in their Diet Coke. As is the Aspergian nature, I’m fanatically organized about some things and disorganized about others, and as luck would have it I lost that piece of paper. I figured someone (maybe me) had thrown it out, but my history teacher found it and gave it to the principal, who called my mother.

She yelled at me for seventy-nine straight minutes, mostly about how violated she felt by my actions, and then she got even more angry because I couldn’t really understand why something I did had upset her. So she took ten of my CrimeBusters notebooks and ran them through her bill shredder page by page, and suddenly, her point was crystal clear. I was so furious that, that night, I dumped the bin of shredded paper over her head while she was asleep.

Luckily, I didn’t get suspended-most of the administration of the school knew me well enough to know I was not a threat to public safety-but my mother’s lesson was enough to make me see why I could never do anything like that again.

I say all this by way of explanation: Impulsiveness is part of what it means to have Asperger’s.

And it never ends well.

I am allowed to work at home on my column, but every Tuesday afternoon I have to trot downtown to meet with my editor. Mostly it’s a therapy session-she tells me what’s wrong with her life and expects me to dole her out advice, the way I do for the masses in the paper.

I don’t mind, because I think that one hour a week of counseling is a pretty fair trade for a paycheck and health insurance. But it also means that on Tuesdays, when Jacob meets with Jess, she is responsible for getting him back to our house.

Tonight, as soon as I walk through the door, I find Theo in the kitchen. “How do you feel?” I ask, pressing my palm against his forehead. “Do you have a fever?”

I’d called home from Burlington, like I usually do before I leave the office, only to find out that Theo was sick and frantic because he’d left school without remembering that today is the day he walks Jacob to his appointment with Jess. A second call to the guidance department kept me from panicking: Mrs. Grenville had talked to Jacob about taking a bus to Jess’s new house and said he felt confident about doing it on his own.

“It’s just a cold,” Theo says, ducking away. “But Jacob’s not home yet and it’s past four-thirty.”

He doesn’t really need to say any more: Jacob would rather saw off his arm with a butter knife than miss an episode of CrimeBusters. But Jacob’s only fifteen minutes later than normal. “Well, he was meeting Jess somewhere new today. Maybe it’s a little farther away than her dorm was.”

“But what if he never got there?” Theo says, visibly upset. “I should have just stayed in school and walked him there like usual-”

“Honey, you were sick. Besides, Mrs. Grenville thought this might be a good opportunity for Jacob to be independent. And I think I’ve got Jess’s new phone number on my email; I can call if it makes you feel better.” I wrap my arms around Theo. It’s been too long since I hugged him; at fifteen, he ducks away from physical affection. But it’s sweet to see him worried about Jacob. There might be friction between them, but at heart, Theo loves his brother. “I’m sure Jacob’s fine, but I’m glad he’s got you looking out for him,” I say, and in that instant, I make a snap decision to capitalize on the goodwill Theo’s feeling for Jacob. “Let’s go out for Chinese tonight,” I suggest, even though eating out is a luxury we can’t afford; plus, it’s harder to find food Jacob can eat if I don’t make it myself.

An unreadable expression crosses Theo’s face, but then he nods. “That would be cool,” he says gruffly, and he slides away from my grasp.

The door to the mudroom opens. “Jacob?” I call, and I go to meet him.

For a moment, I can’t speak. His eyes are wild and his nose is running. His hands flap at his sides as he shoves me into the wall and runs up to his room. “Jacob!”

He has no lock on his bedroom door; I removed it years ago. Now, I push the door open and find Jacob inside his closet, underneath the tendrils of shirt cuffs and sweatpants, rocking back and forth and emitting a high, reedy note from his throat.

“What’s the matter, baby?” I say, getting down on my hands and knees and crawling into the closet, too. I wrap my arms tight around him and start singing:

“I shot the sheriff… but I didn’t shoot the deputy.”

Jacob’s hands are flapping so hard that he is bruising me. “Talk to me,” I say. “Did something happen with Jess?”

At the sound of her name, he arches backward, as if he’s been pierced by a bullet. He starts smacking his head against the wall so hard that it dents the plaster.

“Don’t,” I beg, using every bit of strength I have to drag him forward, so that he cannot hurt himself.