Excerpt from Happiness Is a Chemical in the Brain by Lucia Perillo, plus links to reviews, author biography & more

After a few moments of scrutiny the bartender slides her ID across the table. “What does she want?” the bartender asks me.

One thing Louisa’s figured out is this what-to-do-when-people-refuse-to-speak-to-you routine. “Beer!” she pipes angrily.

“You want me to bring her a light beer?”

“St. Pauli Girl,” Louisa insists. Where she gets this from I don’t know. St. Pauli Girl. But the bartender’s still looking at me.

“Hey, I’m her sister, not her mother. Give her what she wants. She’s not the one driving.” And I order a St. Pauli Girl for myself too, just so Louisa won’t get paranoid that she’s done something weird.

Anyway, the bartender vindicates herself later, by taking care of Finger when he makes his suggestion about taking me outside. Or maybe this is ego talking, my assuming that Finger was bird-dogging me and not my sister, who is after all not a bad-looking woman, especially with her new perm and John Lennon eyeglass frames. I guess the bartender decides to step in as Louisa’s protectress since she thinks I’m being too lax about that job. Bartender says something to Finger underneath her breath, something threatening enough to make his eyes go wide. Then to soothe us all she takes a bunch of change from the till and drops it into the jukebox.

This does the trick: the bar falls silent while the lead guitar knifes its way through the intro. Then, with the grace and synchronicity of ballerinas, all the guys start playing air guitar by strumming the folds of skin around their navels. Finger tilts woozily over his glass, and by the time the song ends his arms are folded on the bar with his head nested inside, whistling the strange birdcalls of sleep.

“Look,” Louisa says, elbowing me. “That funny boy is sleeping.”

“I told you he’s not funny. He’s a jerk.”

“Yeah,” she says, bobbing her head. Often I find myself wishing Louisa did not agree so enthusiastically with everything I say. It forces me to police myself all the time, and this policeman speaks in a voice I recognize as belonging to my mother, who’ll say (as in defense of turning off Louisa’s plumbing), I wish you would start considering your sister’s future more seriously. All I’m trying to do is set things up so that Louisa will be less of a burden when the day comes that neither I nor your father are around.

My mother always gives the words your father an extra jab. He has a new wife who lives with him in a house overlooking the Tacoma Narrows and the bridge that replaced the one they call Galloping Gertie because it turned into Jell-O on a particularly windy day. My mother, on the other hand, is stuck living with Louisa in a trailer, though she becomes offended when I refer to it as such. “It’s a mobile home,” she insists huffily. “And I’ve got the clubhouse. I notice you don’t mind coming down off your high horse whenever you want to use the pool.”

As you can tell, it’s a sore subject—my mother stuck with a clubhouse whose lone assets are a machine that dispenses last year’s Ho Hos, and a pool that can barely accommodate a decent cannonball, while my father’s got Galloping Gertie II and the whole of Puget Sound right in his living room. My mother thought she could salve her pride by hiring a decorator, whose handiwork ended up making the trailer look like the set of a late-night TV talk show, which must remind Louisa all the more about how her life has paled ever since she had to leave the group home, where she could tussle with her girlfriends on the battered furniture every night, like attending summer camp forever. Louisa is simply too big for my mother’s place—and it’s not so much her fatness as the way that her high spirits make her seem loud and clumsy. And my mother takes them as evidence of Louisa’s naïveté and thinks we must band together to fend off evil.

Reprinted from Happiness is a Chemical in the Brain: Stories. Copyright © 2012 by Lucia Perillo. With the permission of the publisher, W.W. Norton & Company, Inc.