Inset left: Kourtney Aumen (Benton County Sheriff”s Office). Inset right: Jessica Mast (Obituary). Background: The Benton County Courthouse in Warsaw, Mo. (Google Maps).
A Missouri woman faces substantial prison time for the death of a little girl she forcibly dunked into a freezing pond.
On Monday, Kourtney Taylor Aumen, 27, pleaded guilty to one count each of second-degree murder and first-degree assault in connection with the December 2020 death of 4-year-old Jessica Joy Mast.
Aumen was previously charged with first-degree murder, assault, armed criminal action, child abuse and child endangerment.
The investigation began when a Benton County deputy arrived at a residence in response to a “possible domestic disturbance.”
Inside, the deputy was led upstairs to the 4-year-old girl.
Jessica was lying on the floor next to bunk beds and wrapped in a pink blanket, authorities said. She was already dead by the time law enforcement arrived. Her body was covered in open wounds from ruptured blisters as well as bruising from apparent belt marks.
But that was not all that killed her, authorities said.
On top of being beaten with a belt, Jessica was repeatedly dunked into a pond on the adjacent property.
That day, the temperature hovered around 40 degrees, law enforcement said. When Jessica was found, there was vomit next to her body, and her hair — pulled back into a ponytail — was still wet from the pond.
The child’s father, James Mast, 34, told investigators that his neighbors across the street — Ethan Mast, 41, who is reportedly not related to the victim, and Aumen — caused the injuries to the girl and other members of James Mast’s family. Also harmed in the incident were a 2-year-old boy and Jessica’s mother, Mary Mast, 35, Law&Crime previously reported.
Aumen and Ethan Mast forced Jessica’s father and mother to comply and watch the beatings, the girl’s father said. Aumen and Ethan Mast ultimately threatened to beat and shoot both parents if they tried to intervene in Aumen and Ethan Mast’s purported efforts to “discipline” the children.
The responding deputy questioned the father on how “he could let people do this to his family.” The father allegedly said they were told the mother had a “demon” inside her, and if this was not addressed, then the children would become like her.
Benton County Sheriff Eric Knox would later refer to the crime as “a religious-type episode” in comments to local media.
Ethan Mast and the parents were also charged in the case and ultimately took plea deals. Ethan Mast pleaded guilty to second-degree murder. James Mast, Jessica’s father, pleaded guilty to second-degree murder and first-degree assault. Jessica’s mother, Mary Mast, pleaded guilty to child endangerment.
Aumen’s trial was scheduled to begin Oct. 26. This week, however, the online docket showed a change-of-plea hearing was held.
The defendant is slated to be sentenced Dec. 21.
