An eighth-grader accused of conspiring with her soldier boyfriend by text message to have her mother killed should remain in an adult jail while awaiting trial, a prosecutor said. Defense attorney John Waldron had filed a petition to have 14-year-old Jamie Silvonek returned to the juvenile facility where she was sent the day after the body of 54-year-old Cheryl Silvonek was discovered last month. Lehigh County District Attorney Jim Martin said Friday he will oppose the petition and Waldron's request to move the case to juvenile court, The Morning Call reported. Adult jail: Jamie Silvonek, the eighth-grader accused of conspiring with her soldier boyfriend by text message to have her mother killed should remain in an adult jail while awaiting trial, a prosecutor said . The teenager is charged as an adult with homicide and criminal conspiracy. Her boyfriend, 20-year-old Caleb Barnes, who is from El Paso, Texas, but was stationed at Fort Meade, Maryland, is charged with homicide. Cheryl Silvonek's body was found stabbed in a shallow grave about 50 miles northwest of Philadelphia. Jamie Silvonek was sent to the county jail this month after she was charged as an adult and is in the women's housing unit, away from older inmates, county officials said. Authorities said Barnes and the teenager met in October, when she was 13, but she told him she was 17. The teen's mother found out about their relationship in early March and ordered them to end it. A day later, the teen told Barnes in a text message, 'I want her gone,' police said. Waldron, however, has said that because of the age difference he believes the teen must have been under 'some type of duress or coercion.' He said his client 'cried incessantly and told me how much she missed her mom' and she feared for her life and that of her father. Barnes' public defender hasn't returned a phone message seeking comment. Accused of murder: 14-year-old Jamie Silvonek allegedly conspired to kill her mother Cheryl Silvonek with her 20-year-old boyfriend 'because she disapproved of their relationship' Barnes, who was on leave from Fort Meade in Maryland at the time of the slaying, was previously charged with homicide. He confessed to stabbing Cheryl Silvonek in the neck multiple times while they were in Silvonek's car, and Jamie Silvonek admitted she was there when he did it and helped dispose of the body, according to an affidavit of probable cause. The teen's attorney, John Waldron, said Thursday he believes his client was under Barnes' control, given the age disparity. 'There has to be some type of duress or coercion,' he said. Waldron said he intends to have Jamie Silvonek examined by a forensic psychologist and will petition to have the case moved to juvenile court. Feared for her life: Silvonek's attorney said the girl tearfully told him she missed her mother, and claimed she was coerced by her soldier boyfriend and afraid for her life . Authorities said Barnes and Jamie Silvonek met in October — when she was 13 — but that she told him she was 17. He joined the military in February of 2012. Barnes graduated advanced training from the Presidio of Monterey, California, and his awards include the Good Conduct Medal and National Defense Service Medal, Army Times reported. Cheryl Silvonek found out about their relationship in early March and ordered the couple to break up, according to court documents. A day later, the teenager told Barnes she wanted her parents dead, the documents said. On March 14, Cheryl Silvonek learned that Barnes intended to take her daughter to a concert in Scranton. Dead: Cheryl Silvonek was allegedly stabbed to death by her daughter's much older boyfriend . 'He is not coming to this house,' Cheryl Silvonek texted to her daughter, who had taken the SAT college entrance exam that morning, according to a police affidavit. The eighth-grader sent her mother a text in response begging her to let them go. 'Mom, if I can't go I'm going to have a mental breakdown,' she said, according to the affidavit. 'I need to go and I need to be with my friends. I feel so desolate mother.' Records show the 14-year-old was upset that her mother had shown her boyfriend her passport as proof that Silvonek was not 17. 'I can't stand her lying to you like this,' Jamie wrote to Barnes. 'SHE IS LYING ABOUT MY AGE,' reported Lehigh Valley Live. Cheryl Silvonek agreed to drive her daughter and Barnes to the show. On their way, the teenager and her boyfriend continued exchanging messages. 'I love you. We can do this. We'll just drive her car then, right?' Jamie wrote, the affidavit said. Barnes replied in a text, 'No. That leaves us as the suspects.' The three drove back to the Silvonek home after the show, and Barnes allegedly stabbed Cheryl Silvonek. The couple then ate at a restaurant and went to Walmart to buy gloves, bleach and other cleaning supplies, authorities said. Police found the body in a shallow grave a few miles from the Silvonek home. The victim's blood-soaked car was found submerged in a pond nearby. Investigators were able to trace the car back to the Silvonek home. When they arrived, they found Barnes, the girl and Silvonek's husband, David. The girl and Barnes were in an upstairs bedroom and the father was still asleep, CBS 13 reported. Barnes was previously charged with criminal homicide, abuse of a corpse and statutory sexual assault. There is evidence he had sex with the girl shortly before the killing, according to police. The 14-year-old was charged earlier with abuse of a corpse, tampering with evidence and hindering apprehension.
A prosecutor said that Jamie Silvonek, 14, accused of conspiring with her soldier boyfriend to kill her mom should remain in an adult jail .
Her boyfriend, 20-year-old Caleb Barnes, who is from El Paso, Texas, but was stationed at Fort Meade, Maryland, is charged with homicide .
Cheryl Silvonek's body was found stabbed in a shallow grave about 50 miles northwest of Philadelphia .
'She threatened to throw me out of the house. I want her gone. ... 'Just do it,' Silvonek allegedly texted Barnes before the killing .