Stolen Babies? Children Caught in Tug of War A tug-of-war over a five-year-old boy is at the center of a national debate over parental rights and immigration, and a sign of what critics say is a growing trend in which immigrants are being deemed unfit parents because they crossed the border illegally. Seth and Melinda Moser of Carthage, Missouri say the boy they call Jamison is their son, and that returning him to his birth mother after five years will cause him untold harm. "I could not love him more, had he come out of me physically," Melinda Moser said in an interview with a Missouri television station. I can only imagine the trauma that he would go through in feeling like people that did love him have betrayed him, you know? His birth mother, Encarnacion Bail Romero, says Carlos was taken from her against her will while she was in federal custody for an immigration-related crime, and hopes to regain custody in a trial that starts later this month. "I'm his mother, I'm the mother of Carlitos," she told ABC News. Watch the full report tonight on "World News With Diane Sawyer" at 6:30 ET and "Nightline" at 11:35 ET. PHOTOS: Tug-of-Love -- Kids Taken from Moms The report is the first in a series from five graduate school journalists chosen to work with the Ross investigative unit as Carnegie Fellows, who found that stepped-up enforcement of immigration laws has had the unintended side effect of wrenching thousands of children away from their parents, sometimes forever. According to a report from the Applied Research Center, "Shattered Families," as of the summer of 2011 an estimated 5,100 children in 22 states were in foster care after their parents were either detained or deported. Immigration attorneys and children's welfare advocates say a small but troubling number, like Jamison, have been put up for adoption to American families after their birth parents were stripped of their parental rights. "It's a massive national problem," said John De Leon, an attorney for the Guatemalan Consulate who worked to help Encarnacion Bail Romero secure a visa to stay in the country while she fights for custody of her son. How many families are involved? "Do the numbers," he said. The ARC report concluded that at least 15,000 more children will face "threats to reunification with their detained and deported mothers and fathers" over the next five years. "I can tell you that if you were to go into any dependency court, any child welfare court in the country today, any community where there are immigrants, this is a problem," De Leon said. In May 2007, when Carlos was just seven months old, his mother was arrested in an immigration raid at the poultry plant where she worked in Missouri. She was charged with aggravated identity theft and sentenced to serve two years in prison, after which she would be deported back to Guatemala. Carlos hasn't seen his mother since. In 2009, three months after Bail Romero was released from prison, the U.S. Supreme Court rejected the use of aggravated identity theft charges in cases like hers. "I started to ask for help and asked what could I do to find out where my son Carlitos was," said Bail Romero. Nobody could help me because I don't speak English. Within months of his mother's arrest, Carlos had been transferred into the custody of a local couple interested in adopting a child. While his mother sat in a jail cell, he began living in his new home full-time. Seth and Melinda Moser Legally Adopt Boy One year later, with Bail Romero unable to understand the language in which the adoption proceedings were being carried out, unable to attend court hearings and despite her statement that she did not want her son to be adopted, Seth and Melinda Moser legally adopted the little boy. Bail Romero got out of prison in 2009 and has been fighting to get her son back ever since. "I never gave my consent for the boy to be adopted by anyone," she said. Still, the judge had ruled that Bail Romero had willfully abandoned her son and couldn't offer him a future. The Mosers, in contrast, were found to be fit parents who were ready to take care of a child. Bail Romero's "lifestyle, that of smuggling herself into a country illegally and committing crimes in this country is not a lifestyle that can provide stability for a child," Circuit Court Judge David C. Dally wrote in his 2008 decision terminating her parental rights. A child cannot be educated in this way, always in hiding or on the run. Dally's judgment had held no mention of Seth Moser's own criminal background. According to court records, Moser, as a teenager, served almost a year in jail after pleading guilty to a felony count involving possession of stolen property. According to Bail Romero's court filings, Moser also has admitted to drug use. The Mosers, through their lawyer, Joseph Hensley, declined to be interviewed by ABC News for this story. Hensley has told the court that Moser has turned his life around since his legal problems as a youth. It wasn't until two months after Dally's decision legally transferred parental rights to the Mosers that Bail Romero was appointed a lawyer by the court. Then, seven months later, Bail Romero was appointed another lawyer, one who was initially contacted by the Mosers. Without any policies in place to regulate the care of U.S. citizen children while their parents are detained, immigrant parents are unable to attend court hearings, contact caseworkers, complete parenting classes or take any of the necessary steps to meet the strict timelines dictated by juvenile courts. "And the result is that nobody is really recognizing that there's a parent there trying desperately to communicate that they want to still be involved with their child," said Nina Rabin, an immigration attorney with the University of Arizona's Immigration Law and Policy Institute. And it's those parents that are slipping through the cracks between two huge bureaucracies, she said. "These are parents that this is happening to, that have the same bond with their children that we have with our children," Rabin said. And to separate them with so little thought and so little flexibility seems beyond any punishment I can think -- I mean, it's worse than any punishment I can think of, to do that to a parent. A spokesman for ICE, the federal government's Immigration and Customs Enforcement agency, said such cases are rare. "ICE is sensitive to the fact that encountering those who violate our immigration laws may impact families," said spokesperson Brian Hale. ICE uses prosecutorial discretion in releasing individuals from ICE custody for humanitarian reasons such as being the sole caregiver of minors and when we are aware that the detention of a non-criminal alien would result in any child (U.S. citizen or not) being left without a parental caregiver. We take great strides to evaluate cases that warrant humanitarian release. READ the full ICE statement. Battle Goes to Missouri Supreme Court Last, year, the custody battle over Carlos landed in the Missouri Supreme Court, where judges called it "a travesty of justice." The court reversed the decision to terminate Bail Romero's rights as a parent and sent the case back to the original court for a retrial, which is set for Feb. 28. Some who push for tougher enforcement of immigration laws say the parents in such cases are to blame. "When parents break the law, they undertake a certain amount of risk that there are going to be consequences," said Daniel Stein of FAIR, the Federation for American Immigration Reform. "Anyone can feel for the torment that this poor woman is going through, recognizing that she doesn't have the educational and the language capabilities to fully defend and vindicate her rights," said Stein. "Nevertheless, she knew she came to this country illegally, she knew she broke the law," he told ABC News. Bail Romero cries and clutches a tiny passport photo of her son as she talks about him. It's the only picture she has of him. She knows that the two no longer speak the same language and that he won't recognize her when he sees her, but she has faith that she will see her son again soon. "I know he needs me," she said. He needs me a lot because I'm the mother of Carlitos. Click Here to Sign Up for Breaking News and Investigation Alerts From The Brian Ross Investigative Unit The Mosers argue that it is better for Carlos to stay with them, not in Guatemala with his mother after her impending deportation. "In terms of best interest, I mean, that almost goes without saying," the Mosers' attorney, Joseph Hensley, told the court in 2008, according to a brief filed by Bail Romero's attorneys. [This] child is an American citizen. The mother is a Guatemalan citizen, and she will be returning to Guatemala. ... I think the best interest standard always weighs very, very, heavily in favor of my clients. Bail Romero says she's thankful to the Mosers for taking care of her son, "but, as Carlitos' mother, I need him to be with me," she said, "because I'm his real mother." This is the first story in a series from the Brian Ross Investigative Unit's 2011 Carnegie Fellows, five student journalists who initiated and led a reporting project on the impact of the federal government's enforcement of immigration law. The journalists are Lauren Gilger, Charles Gorra, Josh Haskell, Robin Respaut, and Selly Thiam. Click Here for the Blotter Homepage.