VASQUEZ, Guatemala -- For years, money from Pittsburgh flowed to this quiet village of cornfields and dirt roads in the verdant central highlands of Guatemala, where good jobs are scarce.

With it, Diego, a subsistence farmer, was able to buy food and clothing and medicine for his ailing wife. He started construction on a two-story house with four bedrooms and space for a small store.

Then, abruptly, the money stopped. The house is now a shell of cement blocks and iron bars with knee-high weeds growing in what was to be a living room. The family's main source of income comes from sewing the long, heavy skirts traditionally worn by Mayan women. It brings them just dollars a day.

The Pittsburgh money stopped because, in the spring of 2005, a Port Authority light-rail train in Dormont struck Diego's son, an undocumented immigrant working in the U.S. under the false identity of Juan Carlos Serrano.

Mr. Serrano, now 25, spent several excruciating months recovering from his injuries in Mercy Hospital. A family friend called his parents and told them their son had lost his right arm, but when Mr. Serrano was well enough to call them himself, he lied, saying he had only broken his arm. He told them he would recover fully.

They still aren't sure about the truth. They speak with him on the phone. But they haven't seen him in eight years.

Mr. Serrano, whose real family name is being withheld by the Post-Gazette because he is in the U.S. illegally, is among an estimated 12 million undocumented immigrants at a time when public officials, both in Pennsylvania and nationally, are engaged in a fierce debate over the future of the nation's immigration policies.

The largest number of migrants comes from Mexico, but millions also have roots in the poorer, smaller nations of Central America, where they face a harrowing overland journey to the United States.

Guatemala, a country of 12 million, has a gross domestic product of about $23 billion and receives at least $3.4 billion each year from Guatemalans living abroad, according to a recent report from the International Organization for Migration.

That money is the country's second largest source of income after coffee.

Nearly 1.4 million Guatemalans live in the U.S., and as many as 60 percent do so illegally, according to Guatemalan government estimates. Most live in big cities, such as Los Angeles and New York, but in recent years, undocumented immigrants have started to find work in new locales. The Pittsburgh region attracts far fewer foreign workers, legal or illegal, than other areas, but the community is growing.

"We are sacrificing a lot to provide a better life for our families," said Alfonso Barquera of the Community Justice Project in Pittsburgh.

As a boy, Mr. Serrano knew nothing of Pennsylvania. He, his parents and his two brothers shared a bedroom with cinderblock walls, a dirt floor, and a shrine to Jesus and the Virgin Mary.

Descendants of the Mayans -- who faced brutal treatment during years of armed conflict with the Guatemalan government -- Mr. Serrano's family lives among the green hills of Vasquez, a village of several thousand inhabitants about two hours from Quetzaltenango, Guatemala's second largest city.

Most speak an indigenous language, K'iche', and some Spanish, which is taught in school. The women wear handwoven guipils, a traditional dress with flower and rainbow patterns.

Mr. Serrano never studied past the third grade. Instead, at age 11, he started working full time. He helped his family grow corn and beans and sew garments, earning about $10 a month.

Mr. Serrano also sold candies on the streets of nearby towns, working from 6 a.m. to midnight.

But, as he matured, he sought a brighter future.

"There was nothing," he said in Spanish in an interview at the Pittsburgh apartment he shares with six Mexican immigrants. "I wanted to build a good house."

The journey

Several friends had already made the trek to the U.S., where jobs were plentiful and where a hard worker could earn $10 to $15 an hour, an unthinkable sum in Mr. Serrano's home village.

His parents thought the 17-year-old was too young for such a journey. But they didn't stop him. His plan was to work for two years and then come back.

"It was his decision," Diego, his father, said last month in an interview at his home. "If God sent him and helped him find a job, good. Although it made me sad."

Diego sold some of his property to help his son raise about $3,000 to pay a local bus owner who smuggled migrants. The night before his trip, the family held a small going-away party. They wouldn't hear from their son again for several months.

Mr. Serrano headed north with about six other Guatemalan men. He carried two pairs of pants, two shirts, two pairs of underwear and about $40 in cash.

The journey through Mexico, mostly by way of trucks and occasionally by foot, lasted one month, with stops in Chiapas, Puebla, Mexico City and Tamaulipas. The travelers slept on the floors of makeshift "hotels" for migrants.

At one stop, a Mexican police officer demanded a $10 bribe.

This year, as many as 149 Guatemalans have died on the trip between their home country and the U.S., according to a recent report in Prensa Libre, Guatemala's main daily newspaper. Many more are injured or robbed en route.

The most harrowing part of the trip, according to Mr. Serrano, came in the Arizona desert, where he and his fellow travelers walked for three days with little water. But the teenager's confidence was strong.

"I always thought, 'I'm going to make it,' " he said.

The group arrived in a small Texas town. They ate a celebratory meal, and then they set off on their own paths. A van carried Mr. Serrano to Morganton, N.C., where a friend and several cousins from Vasquez were waiting for him.

He soon found a job working in a furniture factory, earning $7.50 an hour. He called his parents, who, after months of waiting, had feared the worst.

"Thanks to God," he told them, "I'm here."

Mr. Serrano worked diligently in North Carolina and quickly started sending money home. He became active in a local church, where he played drums and sang spiritual music.

After several years, a recruiter from a chicken processing plant in Pittsburgh's South Hills offered him a higher salary, which he accepted.

His transition was rough. The plant, owned by former Steeler Terry Long, later closed, and Mr. Serrano found himself in a city that once employed thousands of immigrants in its factories, but now offered little.

With the help of a friend, he purchased his new name and Social Security number. He found work at a small furniture business, earning $10 per hour. It was good money, and it helped him hasten the pace toward his main goal: building a new home for himself in Vasquez.

Every two or three months, he would wire $1,000 from Pittsburgh to a bank in Totonicapan, the largest town near Vasquez. His parents had hired a local contractor to start work on his house. It would have a huge living room, several bedrooms and space for a small store.

In April 2005, their son was hoping to return to Guatemala within a few months.

The accident

According to witnesses, Mr. Serrano appeared intoxicated when he walked into the path of the Port Authority train on April 9, 2005. He says he had had only one beer that night. The collision, he says, was just a bizarre mishap.

Mr. Serrano was taken to Mercy Hospital in critical condition, with serious injuries covering his body. His right arm had been severed.

A friend from Vasquez who was living in North Carolina heard about the accident and came to Pittsburgh. He contacted Mr. Serrano's family and told them that he had lost an arm.

The news was terrible blow. His mother's poor health worsened. She later suffered a heart attack.

Diego, 63, still struggles to speak of the terrifying uncertainties surrounding his son's accident. Talking about it, he broke into tears, speaking only in K'iche'. He cradled his head in his hands while his wife and brother-in-law sat beside him.

Indeed, it had been touch and go for his son.

"He was on life support," said Sister Janice Vanderneck, director of social service ministry at the Latino Catholic Community, a diocesan-sponsored center in Oakland. "I truly thought he was going to die." Sister Vanderneck visited for the first time several days after the accident.

Yet Mr. Serrano held on. He woke up in the hospital, thinking he was in his own bed. But he was surrounded by doctors. Sister Vanderneck was the first to tell him that he had lost his arm.

Then he began his difficult recovery process, with Mercy staff guiding him. The hospital does not deny aid to patients who have no proof of citizenship. In 2006, Mercy provided more than $2.6 million in charity care, according to Linda Ross, a hospital spokeswoman.

When Mr. Serrano was healthier, he called his family. He says he withheld the truth about his injuries because of his mother's ongoing health problems. He says he wants to show them in person, when he returns to Vasquez with enough money to start a new life there.

About a year after his accident, Mr. Serrano found a job working at a golf course, earning about $7 an hour. He soon started sending money to his family again, although he didn't make enough to resume work on his future house.

Last month, Mr. Serrano, who now walks with a heavy limp, had to leave the job, saying that his right foot caused him too much pain. An operation was scheduled for last Friday at Mercy Hospital.

But Mr. Serrano still has a positive attitude.

"I'm here and I have to make things good," he said. "I want to do something more."

His goal, at the least, is to put a roof on his house, although that seems like a distant reality.

A few weeks ago, his parents, Diego and Petrona, stood amid the skeleton of Mr. Serrano's house. They haven't been able to pay for further construction in more than two years.

But that isn't their priority. They say they only want to see their son.