CUATRO MILPAS, MEXICO— In this hardscrabble farming village, an American teenager like Luis Martinez was bound to stand out.

Raised on Little Caesars pizzas and Big Gulps, Luis, 13, was portly. The village kids, subsisting on bowls of chicken broth, were all bones and elbows.

Luis wore Air Jordan high-tops. The kids wore sandals made of rubber tires.

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He shot at birds with his BB gun and pedaled around on a Mongoose bike. They scurried up mango trees and chased iguanas.

He seemed like many visitors from America, with new clothes and good health, and the quiet confidence of someone who knew he wouldn't have to endure this place very long.

Then one day Luis and his step-grandfather, Juan Leyva, started standing up sheets of scrap metal on a treeless patch of dirt. They covered the jagged edges with cardboard, straightened the frame and slid corrugated metal sheets atop the walls, fastening it all together with electrical wire.

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The teenager they had treated like a rich American cousin was going to live with his family in a shack, next to a chicken coop.

That summer night in 2010, Luis fell asleep on a squeaky mattress next to his baby sister and his dog-eared Harry Potter book, one of the treasured possessions from his days at James Madison Elementary School in Ogden, Utah.

"He was a very good kid," said Daniel Ibarra, 43, who had watched Luis patch together the shanty on that summer day. "But he was poor — poorer than the poorest person here."

Luis never imagined living a peasant's life in Sinaloa. But like other children whose parents or other family members were deported, he was swept into the current of reverse migration. Thousands of U.S.-born children of former illegal immigrants now live in cities and towns across Mexico. Disoriented by cultural differences and often unable to speak the language, they often struggle, clinging to one another in a society that views them with a mix of envy and pity.

Luis' life spiraled further than most. After Leyva, the breadwinner of the family, was deported in 2010, the family languished in Ogden. Eventually, Dominga Leyva, 49, the boy's maternal grandmother and a U.S. citizen, packed her grandson and his 3-month-old sister, Amor, into their Oldsmobile Alero and drove to the Mexican border town of Nogales.

Juan Leyva got in, and they began the 500-mile drive to the western Mexican state of Sinaloa, passing endless rows of vegetable fields to a one-road village where shirts hung from barbed-wire clotheslines, stray dogs feasted on corn husks and boys playfully swung machetes at stick fences.

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"Dónde está Ooo-tah?" the students asked the chubby-cheeked norteamericano with the gringo accent. Where is Utah?

Luis told them of days ice fishing and snowboarding, of falling asleep on the couch watching horror movies. Back there, he had five video game players, indoor plumbing and shelves full of comics.

It seemed far-fetched; many of the children at the two-room schoolhouse considered them tall tales. When they asked why he came to Mexico, he told them that Leyva had been deported for driving without a license. "They called him a dummy," Luis said.

But Luis could never blame Leyva. His U.S.-born mother, who struggled with drugs, was in prison, and he never knew his biological father. Luis loved his step-grandfather — he called him Dad. Leyva, a wiry man with an easy smile, told everyone that Luis was his son.

In Utah, Leyva had supported the family by working on construction crews, a roofer for all seasons who drew curious stares from passers-by when he pounded shingles in snowstorms. "A man in a car called him 'crazy Mexican,'" Luis recalled proudly.