"The day my boy left," Rosa Maria Gonzalez says in Spanish. "I told him it was the last time I would see him."
She never heard from him again. No one knew whether he was dead or alive.
CBS News correspondent Randall Pinkston reports that three months after he left Mexico, police found a body in the desert near Tucson, Ariz. There was no identification, only bones and some clothing. Most immigrants don't carry any identification to prevent authorities from sending them back.
Mexican consul Juan Calderon says dozens of families call his office in Tucson every month looking for missing relatives, wondering if they are alive, in hiding or buried in U.S. border cemeteries filled with the graves of unknown immigrants.
"We try to help our people immediately," Calderon says.
Calderon now has a high-tech tool for identifying the dead.
It's called SIRLI, Spanish for "System for Identification and Location of Immigrants." Imageware Systems, a U.S. identity management firm designed the program.
Here's how it works: a family in Mexico files a missing person report on a SIRLI terminal, located in every state in Mexico. The family provides any information they have — photos, clothing descriptions, even DNA samples. SIRLI then looks for a match with data in terminals in the United States.
In 12 months, the system has identified at least nine immigrants.
Anyone can understand the pain and agony of trying to find a missing loved one who has likely died. But there is another aspect to the process — the people who literal sift through bones and personal artifacts, gathering information that goes into the computer database.
When U.S. authorities discover and unidentified body they believe is a Mexican national, they contact Mexican authorities, who send people like Oscar Angulo to catalogue personal effects.
"It's pretty hard to tell you the truth," Angulo says of his job. "But it's something that has to be done."
Six months after Avila Gonzalez disappeared, the Mexican consulate in Tucson asked his sister Diana questions about the clothes he was wearing the day he left.
"They wanted to know about his pants," she says. "And everything about his shoes."
Days later, the consulate e-mailed Diana photos from SIRLI.
"I recognized his tennis shoes," she says. "I knew it was him."
A DNA test confirmed the bones and clothes in the Arizona desert belonged to her brother.
Thirteen months after he left home, Olaf Avila Gonzalez's remains were returned to Mexico for burial. Now that his body is at rest, his family has a place to pray for his soul.