(at around 24 mins) Linden is reviewing footage from the Halloween party with Holder. She established the Larsen girl in the footage and then Diablo. There is a close-up of the Larsen girl and she is not wearing her butterfly necklace. In the 1st episode Larsen's mother makes a big deal that she always wears the butterfly necklace and when they found her body in the trunk, the show makes a point to identify the necklace on her.