Adam Montgomery was charged with second-degree murder; tampering with witnesses and informants - which he allegedly did by attempting to coerce Kayla Montgomery, his estranged wife, to lie to investigators; falsifying physical evidence; and abuse of a corpse in the death of his five-year-old daughter, Harmony, as well as second-degree assault charges for a separate incident involving the child. Prosecutors allege that Harmony was murdered on December 7, 2019. Adam, Kayla and Harmony were living in a car. Investigators allege Adam beat Harmony to death in a fit of rage after she had a 'bathroom accident' in the car. Kayla Montgomery, told detectives that Adam repeatedly struck Harmony, who was 5 at the time, in the head in frustration over the accident. Kayla stated that Adam delivered sets of three-to-four blows with a closed fist to Harmony's face/head on three separate occasions over the course of a few minutes'. Harmony died in the car a short while later, at which point Adam and Kayla placed her 'lifeless' body into an Under Armour duffle bag before transferring her body into a cooler. Harmony's body was moved to various locations over the course of the next several months. Kayla told investigators that in either March or May of 2020, Adam rented a U-Haul and during the overnight hours, made a trip to an unknown destination and disposed of Harmony's dead body. Harmony's body has never been found. In a plea deal, Kayla pleaded guilty to unrelated perjury charges and agreed to cooperate with prosecutors in the investigation into Harmony's death. She received a sentence of 3.5 to 7 years in prison, with 1.5 years of the minimum suspended and given credit for time already served.