ALLENTOWN (AP) - Authorities allege that a soldier accused of killing his 14-year-old girlfriend's mother in eastern Pennsylvania after she objected to the difference in their ages purchased a fake birth certificate before the murder.

The (Allentown) Morning Call reports that the detail was revealed during a hearing Monday in preparation for Caleb Barnes' homicide trial in Lehigh County Court in the death of 54-year-old Cheryl Silvonek.Prosecutors allege that Barnes and Jamie Silvonek plotted for a week to kill Cheryl Silvonek, who was stabbed in March 2015 and found in a shallow grave.A judge ruled that prosecutors will able to show jurors text messages allegedly exchanged by Barnes and the teenager during their seven-month relationship along with crime scene photos and recordings of phone calls Barnes made from jail.