Liberty German, 14, and Abigail Williams, 13, go for a hike in a popular park near home. The bodies of the two friends found on Valentine's day. One of the girls videotaped the suspect as he approached, but no arrests have been made.Joining Nancy Grace today:Kelsi German - Libby's SisterBecky Patty - Libby's Grandmother Ashley Willcott - Judge and Trial Attorney, Anchor on Court TVCaryn Stark - NYC PsychologistSheryl McCollum - Director of Atlanta's Cold Case Investigative Research InstituteJoseph Scott Morgan - Professor of Forensics Jacksonville State University, Author of "Blood Beneath My Feet"Alexis Tereszcuk - CrimeOnline Investigative Reporter TIP LINE: Delphi Homicide Investigation Tip Line: 844-459-5786