Lori Vallow's Murder Trial Reveals Grisly Cause of Son's Death.

The cause of death of Lori Vallow Daybell's autistic 7-year-old son, J.J. Vallow, was revealed to be asphyxiation with a plastic bag and duct tape over his mouth, according to forensic pathologist Dr. Garth Warren during her murder trial. J.J. had scratch marks on his neck and bruises on his wrists and ankles where he was bound with duct tape. The cause of death of her daughter, Tylee Ryan, was undetermined, and her autopsy proved to be a grisly challenge. Vallow Daybell is being tried in connection to the murders of her children and her fifth husband's ex-wife, Tammy, and has pleaded not guilty to the crimes.