Harmony Montgomery’s Dad Allegedly Ate Fast Food in His Car While She Died in Back Seat

The last time anyone saw 5-year-old Harmony Montgomery alive was in late 2019. Investigators now believe that her father, Adam Montgomery, 33, killed his daughter in a fit of rage. His murder trial began February 8, and prosecutors laid out details of Harmony's last moments of life and how they believe she died.

Her stepmother, Kayla Montgomery, is also facing charges related to Harmony's disappearance and reportedly worked with police to help prosecute her husband in exchange for a lighter sentence, Fox News reported.

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Before his daughter's death, Montgomery reportedly had a violent past.

The father gained custody of his daughter after his release from prison, despite being a known drug addict and convicted violent felon, Fox News reported. Prosecutors said in court that during his time with Harmony, he and his now-estranged wife, Kayla Montgomery, collected welfare for the child while living in a car. Both parents are accused of being physically abusive toward the young child.

The father reportedly became enraged over his young daughter.

According to prosecutors, Harmony had an accident in her sleep in the car, and when Montgomery realized it, he allegedly beat her mercilessly over the head.

"Kayla was terrified to see what he had done," Assistant New Hampshire Attorney General Christopher Knowles said in court, according to Fox News. "She could hear the moaning – sounds that eventually stopped."

The father allegedly told his wife that he was afraid he hurt her during the beating.

Despite Harmony's physical injuries, the couple allegedly went to get drugs.

Prosecutors said Montgomery and his wife went to a methadone clinic to obtain drugs and then ate fast food, all while the young girl lay helpless in the vehicle behind them. When he realized Harmony was dead, Adam Montgomery allegedly stuffed her body into a duffle bag that he then carried with him for weeks before disposing of her body, Fox News reported.

Kayla Montgomery is also facing charges.

The stepmother is accused of illegally collecting welfare benefits on behalf of Harmony for months after she knew the child had died. As part of a plea deal, Kayla Montgomery told investigators that her husband killed Harmony and carried her body around for months before disposing of her remains somewhere outside of Boston, Fox News reported. The exact location is unknown, but investigators reportedly found DNA in the area.

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Police are still looking for Harmony's remains.

As the trial continues, investigators are determined to find Harmony's body and asked anyone with information to contact a tip line dedicated to the case at 603-203-6060.

Her father, who was not present in court during the opening statements, is already serving a 32-year prison sentence for an unrelated weapons charge. If he is convicted of Harmony's murder, however, he may never see life outside of prison again.

If you suspect child abuse, you can call the Childhelp National Child Abuse Hotline at 1-800-422-4453 (1-800-4-A-Child) or go to Childhelp.org. The hotline is available 24/7.