Few activities are more consistently prone to chaos and misadventure than spontaneous road trips with extended family. You can talk about togetherness and family bonds till Congress passes the Federal Marriage Amendment, but cram a bunch of cranky, high-strung, quirky relatives into a vehicle for a few days on the road, and all bets are off — except, of course, that hilarity will ensue.

Little Miss Sunshine is about just such a trip. Brash, riotous, and utterly endearing, it is a film that dares to crawl over the back seat and demand to know, “Are we there yet?” Like those sugar-wired kids insistently asking when the fun will arrive, it is both maddening and irresistibly cute, a film that revels in how dismally not together family togetherness can be. It is a movie about breakdowns, not just of rickety old busses, but of families and individuals too. But most importantly, it is about keeping your foot on the gas while cruising down a highway where all the exits lead to failure. When all else fails — and unquestionably, all will fail — go for broke.

Little Miss Sunshine works as an incubator for misery, feeding it, nurturing it, watching minor trials grow into soul-crushing failures. The subjects under the lab lights here are the all-too typical members of a fragmented middle-class family — mom, dad, teenage son, and elementary-school daughter — plus a foul-mouthed grandfather and dad’s gay, post-suicide brother. This cantankerous crew must come together, if only in physical proximity, when daughter Olive (a sprightly, wonder-eye Abigail Breslin) gets a chance to fulfill her dreams of beauty-pageant stardom. After a bit of family-style negotiation (translation: heated argument), they pack up their petty arguments and personal shortcomings to hit the road in a beat up VW. What follows is a raucous, sometimes coarse, and frequently hilarious look at the potholes and traffic jams of family life. It’s fun with the whole family, if certainly not for it.

Rarely has any movie conjured up a more ornery clan of self-deluded narcissists. There is the father, Richard (Greg Kinnear), a struggling self-help guru who desperately clings to his personal-fulfillment shtick, shoving it into the least appropriate moments in hopes that he can convince someone to buy it. There is Grandpa (Alan Arkin), an uncouth, casually vulgar codger who flaunts his apathy toward the rules of politeness. There is Frank (Steve Carrell), Richard’s depressive, gay, Proust-scholar brother, fresh from a failed suicide, a disastrous relationship, and a professional meltdown. There are Sheryl and Dwayne (Toni Collette and Paul Dano), a flustered mother always playing family referee and an angry-at-everything, Nietzsche-idolizing son who refuses to speak. The family is a case study of disconnection and dysfunction — a homegrown garden of exquisitely cultivated psychological hang-ups. Their unspoken credo is you are your neurosis. The exception, though, is Olive. Oh, to be sure, she is as thoroughly bonkers as anyone in the family, a slightly chubby young outcast with oversized glasses and a penchant for fanciful outfits. Pinballing wildly off her cranky relatives, she’s jittery with unkempt energy and fantasies of beauty queen stardom, even though she lacks the slightest resemblance to the sequin-covered child dolls with whom she is destined to compete. She is not and never will be beauty pageant material, yet this thought never crosses her blissfully innocent mind. Always sunny, she is a buoyant island of sweetness and hope amidst an encroaching sea of cynicism and negativity. Little Miss Sunshine is the rare film which recognizes that failure and disappointment are a part of life — often a disproportionately large part — yet celebrates those who live it up anyway.

It’s a road movie that fills its tank with madcap disaster and unholy outrage, yet never crashes into pure bile; it’s like a play written by Christopher Durang if he weren’t such a willful nihilist. Structurally, it’s a one-trick film: Take an awkward, humiliating situation that lesser comedies would leave as-is, then pile on the misery. Nothing is so bad it can’t be made worse (or funnier). Life, in this film’s view, is an unending string of catastrophes.

If this tendency toward antic excess is what largely steers the laughs, it is also what causes the film to occasionally swerve into the median. The movie’s desire to continually top itself leads it to ever-loftier heights of absurdity. By the time the climax rolls around, both the family and the film have lost all control of themselves. It’s a riot, no doubt, but it is also something of a mess.

Of course, this is also part of the point. Families, all too often, are a mess, and Little Miss Sunshine reminds us that the building blocks of civil society can be remarkably uncivil. To those inside them, they can seem like breeding grounds for irritation and insanity. And yet, for all their imperfections, families are not just important — they are the most important thing. After all, if your family won’t put up with your craziness, who will?

“The difference between winners and losers,” Richard explains in his self-help course, “is that winners don’t give up.” Notice that he doesn’t say they succeed. The trick, then, is to refuse to succumb to the succession of indignities that inevitably blows out a few tires in every life. And though families may often be the source of such indignities, they are also the support mechanism for living through them, squabbles, quirks, irritating mannerisms and all. In Little Miss Sunshine, those quirks aren’t just to be survived: They’re to be celebrated. When a cop flags down Olive’s family, Richard quickly hushes their bickering. “Everybody just pretend to be normal, okay? Like everything’s normal here.” Not a chance.

– Peter Suderman is assistant editorial director at the Competitive Enterprise Institute. He blogs on film and culture at www.alarm-alarm.com.