ABC News' 20/20 Interviews Mothers Of Teenage Girls Who Stabbed 12 Year Old Friend 19 Times 2/17

It is every parent's nightmare. After 12-year-old Payton Leutner was invited to a sleepover, her two 12-year-old friends stabbed her 19 times leaving her for dead in the Wisconsin woods. The defendants Morgan Geyser and Anissa Weier claim they committed the horrendous attack to appease a mysterious fictional character - known as Slender Man. After a judge determines how long Morgan will be placed under state mental commitment this week, "20/20" features interviews with mothers of the perpetrators - Angie Geyser and Kristi Weier. The hour, anchored by ABC News' David Muir, includes interviews with Morgan and Anissa's families; Dr. Melissa Westendorf, a forensic psychologist involved in the case; Anthony Cotton, Geyser's defense attorney; and Waukesha County Assistant District Attorney Kevin Osborne who prosecuted the case. "20/20" airs Saturday, Feb. 17 (10:00-11:00 p.m. EST), on ABC. (Rebroadcast. OAD: 2/2/18)

After THE ATTACK in May 2014, Payton found the strength to crawl out of the woods and was spotted by a passing bicyclist who called 911. Morgan and Anissa fled the scene and were missing for five hours before authorities apprehended them along Interstate 94. The case has taken years to make its way through the legal system mainly because of a disagreement over whether the girls should be charged as adults or juveniles. Ultimately, they both remained charged as adults with first degree attempted intentional homicide. Anissa accepted a deal to plead guilty to attempted second-degree intentional homicide, and a jury found her not guilty determining she was not responsible due to mental illness at the time of the crime. A judge ordered her under a state mental commitment for 25 years, with credit for time served. Morgan pleaded guilty as originally charged in exchange for prosecutors not holding her criminally responsible for her actions due to mental illness.

This is the third "20/20" report on the Slender Man attack. In 2014, Muir had the only interview ever with Payton's parents who described the harrowing sequence of events of that fateful day that changed their lives, and SURVIVOR Payton courageously revealed her identity and resolve for the first time in the special.

"20/20" is anchored by Elizabeth Vargas and David Muir. David Sloan is senior executive producer