15-year-old Candice Parchment went missing in April of 2010. Police found her remains beneath a mattress in a wooded and secluded area in November of 2010. They finally got a break in the case when they read Candice's own diary where she described a previous attack by two other teenagers, Marshae Hickman and Jermaine Robinson.
https://www.drinkingthecoolaid.com/
Resources:
Who was Candice Parchment and how did she die? | The US Sun (the-sun.com)
Man found guilty of murdering teenage girl – WSB-TV Channel 2 - Atlanta (wsbtv.com)
Watched: How I Caught My Killer Season 1 Ep 2 I found Candice’s Diary on Hulu