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.