BARCELONA, Spain — Antonio Barroso cried himself to sleep every night until he was 12, haunted, he says, by a taunt from other children: "Your mother isn't your real mother."

He asked his mother repeatedly, and even secretly checked his official birth certificate. But she insisted, and the documents confirmed, he was her son.

It wasn’t until 2008, when he was 38, that he discovered the lie: He was stolen from his biological parents and sold into adoption.

“My old friend Juan Luis called me one day and told me our parents bought us from a nun in Zaragoza." Barroso, 42, told GlobalPost, recalling the chain of events that changed his life. “It was his father’s deathbed confession.”

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His story is one of hundreds that have come to light in Spain over the past two years. No one really knows for sure how many of these cases exist. Enrique Vila, a Barcelona lawyer who specializes in adoptions, estimates there might be as many as 300,000, about 15 percent of the total adoptions that took place in Spain between 1960 and 1989. At the moment, more than 900 cases are being investigated by regional prosecutors across the country. That amount is increasing every month.

After his friend’s revelation, Barroso secretly checked his DNA against his mother's. The results showed that there was no chance she was his biological parent.

He confronted her. She finally admitted that she paid 200,000 pesetas (about 1,200 euros) for Barroso — an enormous sum in 1969, particularly for factory workers like Barroso's parents. Spain at the time was a poor country, struggling under the dictatorship of General Francisco Franco.

“That was the price of an apartment back then," Barroso said. "My parents paid it in installments over the course of 10 years because they did not have enough money.”

Barroso said his mother told him the nun who sold him and his friend was Montserrat Vivas Llorens. Her name also appears in police reports on the case. Since then, the two men have twice traveled the 165 miles to visit Llorens. Last year, their efforts paid off: She told Barroso that another nun had asked her for "two children for the Penedès region."

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“Your cases were special,” she told Barroso on a taped recording. “(Because) your parents were friends of friends of Montserrat Rius, another nun.”

The Catholic church declined to comment on the matter. The Spanish Confederation of Religious Orders, a prominent Catholic organization, declined to comment due to the ongoing investigation. But a spokesperson added that the cases are "very unpleasant" and hope that the full weight of the law is applied to the perpetrators "whether they were members of a religious order or not."

Llorens, who is over 80, has not been charged in the case, which is under investigation. GlobalPost’s efforts to contact her were unsuccessful. The second nun, Rius is deceased.

Despite the staggering numbers and the fact that these cases are spread across Spain, prosecutors say they don't believe it was a "baby mafia," but a macabre business involving public and private hospitals, doctors, nurses, midwives and even nuns who wanted to make money.

Typically, doctors and nuns would tell mothers their babies had been born dead, or that they had died shortly after birth, Barroso said. Then they would sell the newborns to adoptive parents and forge all official documents. After being told their newborns died, mothers would usually request to see their children, but doctors and midwives would deter them.

This is what Barroso learned when he started digging for answers.

A quest for answers

Determined to find the truth about their origins and similar cases, Barroso and Juan Luis Moreno founded the National Association for Victims of Irregular Adoptions (ANADIR), a support group dedicated to shedding light on the issue.

Since February 2010, more than 1,800 people searching for their blood relatives have joined. ANADIR has set up its own DNA bank and every Friday, a lab crosses the genetic profile of members looking for matches. So far, they have reunited five families through this profiling.

In most of the cases ANADIR handles, he says it has been the siblings of stolen children that have led the search. The biological mothers are usually too emotionally devastated to address what happened. For decades, these mothers maintained that their newborn babies had been stolen after birth. No one believed them. It was not until the first cases popped up in the media two years ago and the Spanish Parliament took notice that family members began to listen.

“The midwife told my mother she would have a horrible image that would stay with her for the rest of her life,” says Sandra Mateo, who is searching for her brother. (Mateo, like the other victims in this article, was referred to GlobalPost by ANADIR.)

Her mother held her baby for more than six hours before he was taken away, she says. “Doctors told her he died from suffocation because the umbilical cord had wound around his neck during delivery three times,” says Mateo. “That is ridiculous. If that had been the case, he would have not been put into my mother's arms.” Her mother never saw her brother's corpse.

Most of these mothers, already traumatized like Mateo’s, would resign themselves to what they were told. Others, though, insisted on seeing their lifeless babies. In certain hospitals, they would be shown a dead baby, “always the same one,” explained Barroso, who has heard these almost-identical stories many times. “It is terrible to hear some mothers say that all they remember is a cold kiss: The baby they were shown had long died and was frozen.”

The story of 31-year-old Gemma Ríos, of Montcada i Reixac, near Barcelona, took a particularly eerie turn several years ago.

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Ríos mother always maintained that she gave birth to twins in Barcelona on April 25, 1980. “I never believed her,” said Ríos, who is now looking for her sibling.

Ríos's mother told her that three gynecologists had confirmed that she was pregnant with twins “because they could clearly hear three hearts,” Ríos said. But to her mother's surprise, during labor, the doctor told her there was only one baby and what followed Ríos' birth was the placenta. Ríos says her mother recalls a midwife quickly turning around and leaving with the organ “in her arms, which is strange because a placenta is like a liver, you cannot carry it like that.”

Rios says that in the medical records from her delivery, much of the details are blacked out.

She is convinced that the answer lies in a painful scar the size of a fingertip she’s had on the crown of her head since birth. "After years of asking physicians and not getting a good answer, a doctor told me a few months ago that it resulted from having being slightly attached to another baby in my mother’s womb,” she said. “This tallies with my mom’s version that while she was pushing me out, doctors were using a lot of utensils. I think they were separating us.”

Several years ago, when she was out with her mother, Ríos ran into a friend on the street. “Why you didn’t say hello to me the other day in L’Hospitalet?" he asked, referring to a town near Barcelona. "I was calling out to you from my car.” Ríos told him she had never been in L’Hospitalet, and that it must have been someone who resembled her. The friend insisted, “She was just like you, Gemma, just like you.” Ríos’ mother immediately grew emotional. Had the friend seen Rios’ missing twin?

Government steps in

In 1987, the law was changed in Spain and the government began regulating adoptions, taking over the job from hospitals. Until then, the death of a baby had to be noted in medical documents but many of the official papers at ANADIR’s headquarters obtained from medical facilities lack data or have incorrect data filled in. Also, according to Spanish law, babies dying in the first 24 hours are considered fetuses, so they are buried in coffins in mass graves. This makes it difficult for relatives to exhume the corpses and test DNA.

Some families, though, have pushed to exhume the bodies of their children. Many have found empty coffins, says Barroso. This comes as no shock to Antonio Jiménez, who drove hearses for a Granada funeral homes between 1979 and 1988, and often served Mothers and Children Hospital there.

“There were at least 20 times in which they gave me packages that were the size of a newborn but very light, like feathers, [a half pound] at the most,” he said. “I used to think they were only putting the placenta there because the shape of the bundle wrapped with bandages made no sense: There was no head, no legs, no nothing.”

These cases are difficult to investigate because they happened decades ago. Still, prosecutors say they are currently gathering enough evidence to bring charges against those responsible, a list that includes doctors, nuns, midwives and officials.

Adoptive parents are also coming under scrutiny.

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Some adoptive mothers were directed to fake pregnancies by putting pillows under their clothes, Barroso, said, adding that most were lied to as well. The nun told his mother that his biological mother was a drug addict who did not want to keep him. “My adoptive parents thought they were doing something legal, and that the money went for the documents, doctors, and so on,” he said.

He says he believes his mother when she told him that. But in his eyes, it is easy to see that he needs to. His entire past is a lie, he says, one that began with his birth certificate. Now he is hoping it might end with the truth and maybe even a newly discovered sibling.

“I just want to know who I really am," he said. “The first time my DNA was crossed with someone who I thought could be my sister, my hopes shot up. It was the closest I’ve ever been to having a real sister.”