Lori Vallow murder trial: J.J. Vallow, Tylee Ryan cause of death revealed | LiveNOW from FOX

A forensic pathologist testified on Week 4 of the Lori Vallow murder trial about how J.J. Vallow and Tylee Ryan died. The so-called "Doomsday mom" is accused of killing her two youngest kids, ages 7 and 16. Their bodies were found buried on Chad Daybell's property. Authorities determined that 7-year-old J.J. died of asphyxia with a plastic bag over his head. The coroner also said the manner of Tylee Ryan's death was a homicide, but the cause of death remains unknown. The teen's remains were found severely decomposed and had been badly burned. FOX 10 investigative reporter Justin Lum joined LiveNOW's Andrew Craft to discuss the emotional day in court. More LiveNOW from FOX streaming video