A 14-year-old Pennsylvania girl allegedly conspired with her 20-year-old soldier boyfriend to have her mother killed, texting him hours before the woman was stabbed to death, 'I want her gone,' it emerged today. Jamie Silvonek was charged as an adult with homicide and criminal conspiracy, Lehigh County District Attorney Jim Martin announced Thursday. Cheryl Silvonek, 54, was fatally stabbed in the driveway of her Upper Macungie Township home early March 15, hours after taking Jamie Silvonek and the eighth-grader's boyfriend, Army Spc. Caleb Barnes, to a concert, according to court documents. Scroll down for video . Star-crossed lovers: Jamie Silvonek (left), 14, and her boyfriend, 20-year-old Army Spc Caleb Barnes (right), have been charged with killing the girl's mother for trying to break them up . 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. Slain in cold blood: Cheryl Silvonek, 54, was stabbed several times in the neck inside her car after driving her daughter and Barnes from a concert . 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. 'She cried incessantly and told me how much she missed her mom, and told me she was coerced, she was afraid she was going to be killed, she was afraid her dad was going to be killed,' Waldron told The Associated Press. 'So there's a lot of things we have to decipher here.' 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. '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. Police found the victim's blood-soaked car submerged in a pond and traced it to the Silvonek family's home in Upper Macungie Township (pictured) 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 . 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.' The teenager then texted Barnes: 'She threatened to throw me out of the house. I want her gone,' the affidavit said. Later, she allegedly wrote to him: 'Just do it.' 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. Lies: Barnes and Jamie Silvonek met in October — when she was 13 — but that she told him she was 17 . 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.
Jamie Silvonek, 14, was charged as adult with homicide and criminal conspiracy in her mother's stabbing death .
Silvonek's 20-year-old boyfriend, Army Spc. Caleb Barnes, is accused of stabbing teen's mother in the neck March 15 .
'She threatened to throw me out of the house. I want her gone. ... 'Just do it,' Silvonek allegedly texted Barnes .
Cheryl Silvonek's body was buried in shallow grave near her home in Pennsylvania .
Affidavit states Silvonek and Barnes when to a restaurant after the stabbing and then drove to Walmart to buy gloves and bleach .
Police found victim's blood-soaked car submerged in a pond and traced it to Silvonek family .
Silvonek's attorney said the girl tearfully told him she missed her mother and claimed she was coerced .