Despite his internal and external injuries, the boy's father and his girlfriend insisted he had fallen
Tate Thurman

An Illinois woman is accused of beating her boyfriend’s 4-year-old son to death and then claiming he died after slipping on a wet floor.

Lesli Jett, 33, has pleaded not guilty to three counts of first-degree murder with intent to kill a child under the age of 12 and one county of aggravated battery, WMBD, Mix1068 and the Journal Star report. If found guilty on any of the murder counts, she faces up to 100 years in prison.

Jett was accused of murdering her boyfriend’s son, Tate “T.T.” Thurman, after the boy was found unresponsive by first responders on Feb. 18.

Jett had called 911 that day to report the boy was suffering from cardiac arrest. But first responders who came to the family’s East Peoria home called police because Tate’s body was covered in bruises and Jett’s phone call had seemed suspicious to them.

Jett allegedly claimed the boy had “slipped on some water and fell on the floor and immediately became unresponsive,” according to a probable cause affidavit obtained by multiple outlets.

Only Jett and another child, 2, who was sleeping, was home at the time of the incident, according to the affidavit.

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Tate was transported to a hospital in critical condition, where doctors found he was suffering from internal bleeding due to a large intestinal tear. His body was also covered in extensive bruising and lacerations. Doctors believe Tate fell into a coma 30 minutes after the bleeding began.

Lesli Jett
Lesli Jett

Two days later, Tate succumbed to his injuries without ever regaining consciousness. Jett and Tate’s father have insisted that the injuries were from his fall and not abuse.

On Thursday, the Peoria County Coroner said Tate’s injuries were “grossly inconsistent” with Jett’s story, WMBD reports.

An autopsy found Tate also suffered from a fractured collarbone, deep muscular bruising and extensive contusions and abrasions across his body, including his buttocks and genital area.

Jett’s bond was set at $3 million. Her public defender could not be reached for comment Friday.

If you suspect child abuse, call the Childhelp National Child Abuse Hotline at 1-800-4-A-Child or 1-800-422-4453, or go to All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.