NASHVILLE (AP) — A woman was sentenced Monday to 20 years in prison for kidnapping a 4-day-old boy in Tennessee while claiming to be an immigration agent.Tammy Silas of Ardmore, Ala., was sentenced by U.S. District Judge Todd Campbell for her guilty plea in the 2009 kidnapping of Yair Anthony Carillo.According to the plea agreement, Silas targeted Maria Gurrolla, a native Mexican, at a food assistance office and went to her home. Authorities say Silas, 39 at the time, stabbed the woman and snatched away the baby, who was found unharmed three days later at Silas' home in Alabama.No ransom was ever requested, and Silas apparently just wanted a child, according to officials.Silas told the court she would be unable to pay the more than $30,000 in restitution that the judge has ordered."I have had nothing ... never will," she said tearfully.Gurrolla, who was 30 at the time, told the court on Monday that her family is still affected by the kidnapping. She said her three other children have struggled in school and have nightmares."It's impossible to put down on paper the suffering," said Gurrolla, whose statement in Spanish was translated into English by an interpreter.