A Rock County judge ruled this week that Dayveon Lathrop is competent to stand trial on charges that he fatally stabbed his 8-year-old adopted sister and hid her body in a tote in the family’s laundry room, clearing the case to proceed after months of psychiatric evaluations and schedule changes.
The ruling advances a homicide case that began in March 2024, when detectives said the girl was reported missing from a home on West Miles Road in the Town of Fulton and later discovered dead. Lathrop, now 21, is charged with first-degree intentional homicide and hiding a corpse. He pleaded not guilty the following June. Competency became a contested issue through 2024 and 2025, with one judge finding him fit for trial and, later, another deeming him unfit and ordering treatment. Monday’s finding returns the case to the regular track and sets the stage for a jury trial in Rock County in mid-2026.
According to a criminal complaint, the girl’s father called authorities on the evening of March 9, 2024, after he could not find his daughter. When he confronted Lathrop, who had been the only person at home with the child while the father ran errands, Lathrop responded, “She is dead,” the complaint states. Deputies and a township officer searched the home and surrounding area. Investigators later said they recovered two knives from a shower and found the child’s body in a plastic tote in the basement laundry room. The Rock County Medical Examiner’s Office determined the girl died from stab wounds. Lathrop was arrested the next day and booked into the county jail.
Court records show that at his first appearance in March 2024, the question of Lathrop’s competency was raised and a report was ordered. He was found competent at a May 2024 hearing and entered not-guilty pleas in June. A jury trial was set for July 2025, but the date was removed when the defense requested another evaluation in June 2025. In July, the court found Lathrop not competent, and he was committed for treatment. After months of restoration efforts, a third hearing was held on Dec. 29, 2025. The court concluded he had been restored to competency and transferred him back to the Rock County Jail pending trial.
Authorities have not released the child’s name publicly in recent court filings. The complaint indicates neighbors reported seeing a verbal dispute between Lathrop and the child around 4:30 p.m. the day she was reported missing. Detectives documented the discovery of the body and the recovery of edged weapons as evidence. The sheriff’s office previously said additional counts tied to child neglect, drug paraphernalia and bail jumping were noted at the time of arrest; the homicide and hiding-a-corpse charges remain the central counts before the court. No additional suspects have been named. Officials have not outlined a motive and say the reason for the killing is unknown.
The Town of Fulton home sits between Janesville and Madison near the Rock River, in a quiet stretch of Rock County where rural roads feed into small subdivisions. The case drew significant attention in spring 2024 as search crews, crime-scene vans and patrol cars clustered on West Miles Road. Parents and children from the area left flowers near a roadside mailbox. Court hearings since then have traced the procedural back-and-forth common to cases where mental competency is disputed, including ordered reports by psychologists, commitments, and repeat reviews to determine whether a defendant can understand the proceedings and assist counsel.
Monday’s ruling shifts the focus to the next legal steps. The court scheduled a jury trial to begin July 20, 2026, with a series of check-ins beforehand to keep the case on track. A status conference is set for May 8, 2026. Prosecutors say they will proceed on the homicide and hiding-a-corpse counts, which carry maximum penalties of life in prison and additional years if convicted. Pretrial litigation is expected to address evidentiary questions around the knives, the recorded statements attributed to Lathrop, and expert testimony concerning competency and any intoxication claims noted in the complaint.
Outside the courthouse, the case remains a touchstone for grief in Rock County. In earlier hearings, relatives sat in the gallery as prosecutors summarized the complaint and defense attorneys pressed for mental-health evaluations. No formal victim-impact statements have been presented yet; those typically come at sentencing if a conviction is entered. Residents who followed the case said the timeline, stretching from the child’s disappearance through the competency reversals, has been difficult. A small memorial at the roadside was removed after the initial investigation ended, and neighbors say they are waiting for a full accounting at trial.
As of Wednesday, Dec. 31, the court’s competency finding stands, Lathrop remains in the Rock County Jail, and trial preparations are underway. The next milestone is a spring status hearing, followed by final pretrial deadlines ahead of jury selection in July 2026.
Author note: Last updated December 31, 2025.