Court records say the 14-year-old was found dead after a welfare check at a home in the Town of Turtle.
JANESVILLE, Wis. — A Wisconsin mother has been charged with first-degree intentional homicide after investigators said her 14-year-old daughter was found stabbed to death at a home in the Town of Turtle, a case that began with a welfare check and moved quickly into Rock County court.
Authorities say Tyiece Oninski, 41, admitted in a call to Rock County dispatch that she had killed her daughter, Kuren Rein, then tried to take her own life. The case matters now because prosecutors have filed the most serious homicide charge under Wisconsin law, the victim has been publicly identified by family members, and investigators have begun laying out the evidence they say supports the charge. Court records show Oninski is being held on a $1 million cash bond, with another court appearance scheduled for April 14.
Deputies and other first responders were sent to a home in the 2000 block of East Gorton Street shortly before 8 a.m. on March 20 for a welfare check. By the time they arrived, the case had already taken an unusual turn. According to the criminal complaint described in local reports, Oninski had called the county’s non-emergency communications line and said she had killed her daughter the night before. During the call, dispatchers asked whether she wanted medical help for the girl. The complaint says Oninski answered, “She’s dead, honey. She needs a hearse.” Deputies then entered the home and found Rein dead inside. Officers also found Oninski injured, with wounds to her neck, wrists and face or temple area, according to the complaint. She was taken first to Beloit Memorial Hospital and later transferred for more treatment. The sheriff’s office arrested her after the scene was secured.
As the investigation moved from the house to the courtroom, more detail came from the criminal complaint. Investigators said the call with dispatch lasted more than 13 minutes and included Oninski saying she had killed her daughter “to protect her from somebody else.” The complaint, as reported by local stations, says she later named Elon Musk as the person she believed posed a threat. Authorities have not publicly described any evidence connecting Musk to the family or explaining why Oninski believed that. Prosecutors instead focused on the physical evidence collected at the home. Officers reported finding a black pocketknife and an empty leather sheath near Rein’s body. A detective also noticed a partial barefoot print in the residence and later saw red staining on the bottom of Oninski’s left foot, according to the complaint. Toxicology results cited in court reporting said Oninski’s blood tested positive for benzodiazepines, amphetamines and THC after she was hospitalized.
The medical findings added a sharper picture of what investigators say happened inside the home. Reports based on the complaint and later court coverage say the Rock County Medical Examiner’s Department determined Rein died from deep incised wounds on the right side of her neck. The same reporting said there were no defensive wounds noted in the findings described in open court and in the complaint. Investigators also interviewed the homeowner, described in reports as a grandfather figure to Rein, who said he had been asleep and believed the girl had already left for school. His bedroom was separated from the sleeping area used by Oninski and Rein. That detail became part of the timeline prosecutors used to suggest the killing happened during the night or before the morning call. The complaint alleges the attack happened March 19, with the confession call coming the next morning. Authorities have not publicly released a fuller reconstruction of the hours between the alleged killing and the welfare check.
The death shook a part of Rock County that local officials described as usually quiet. Town of Turtle Police Chief Timothy Stec told local television reporters the case was especially painful because it touched more than one community and involved school connections and a large circle of friends. Stec also said the town’s last homicide was in 2011, underscoring how rare such a case is there. Rein was later identified by family members, and court coverage said she was a freshman at Beloit Memorial High School. In a statement shared with WMTV, her aunt described her as “kind, intelligent” and deeply optimistic. Family members also began raising money for funeral expenses. Those details have widened the story beyond the criminal complaint, showing how the case has spread through schools, neighboring communities and extended family networks that are now dealing with the loss of a teenage girl as the legal case moves forward.
The legal process is still in its early stage, but several points are already clear. Oninski is charged with first-degree intentional homicide, a Class A felony in Wisconsin that can carry a life sentence if she is convicted. During a recent court appearance, attorneys argued over whether she posed a danger beyond the home where the killing happened. Defense attorney Matt Lantta argued in court, as reported by WISN, that the risk appeared tied to Oninski and the victim. Prosecutor Richard Jay Sullivan answered that an unprovoked fatal attack on a 14-year-old child was serious enough to support a high bond. The judge ordered a $1 million cash bond and set an adjourned initial appearance for April 14. As of April 1, no additional charges had been publicly announced, and authorities had not said whether mental health evaluations, further forensic testing or plea discussions were underway. The sheriff’s office and medical examiner’s office have both remained part of the ongoing investigation.
The public record also leaves several important questions unanswered. Authorities have not said whether anyone besides Oninski and Rein was awake when the killing happened, whether there had been earlier police calls to the home, or whether investigators found written notes, digital records or other evidence that might explain the motive claim in the complaint. They also have not released more detail about Rein’s last known hours before she was found dead. What is clear is that the case began not with a long missing-person inquiry or a street-side crime scene, but with a call from inside the home itself, followed by a fast response from deputies and a quick move into homicide court. That sequence has made the complaint central to public understanding of the case, even as prosecutors and investigators continue to sort out what evidence they may eventually present if the case goes to trial.
As of April 1, Oninski remained jailed in Rock County on the homicide charge, and the next public milestone in the case was a scheduled court appearance on April 14.
Author note: Last updated April 1, 2026.