when rebecca checked her voicemail just before 1:00 a.m., sergeant nemeth said she heard a grim message from her boyfriend, max's dad, jonah. >> that message that was left on her phone was to inform rebecca of max's grave condition and imminent death. >> reporter: did rebecca blame herself for the child's severe injuries and then take her own life? the sergeant showed photos from inside the bedroom where rebecca spent her final moments. there was a rope tied to the bed. the other end had been looped around rebecca's neck. there were also two knives in the bedroom, apparently used to cut the rope. everything was swabbed for dna. >> dna profiles were only from rebecca. >> reporter: so what about rebecca's hands and feet being tied? didn't that show another person was involved? sergeant nemeth said it did not. >> we conducted an experiment to determine if it is possible for a person to secure their hands behind their back in the fashion we found. >> reporter: they even showed a video demonstration. and while tying one's hands in a suicide is uncommon, the medical examiner said it's not unh