WARNING: This story contains graphic content.

An Illinois woman charged with killing her two-year-old son had been closely following the murder trial of Massachusetts mother Lindsay Clancy and was texting friends about the case just hours before her son was found dead, prosecutors said.

Corie Walsh, 40, was charged with three counts of first-degree murder after her son, Barrett, was found dead in the basement of the family’s suburban Chicago home on September 1, according to court records obtained by NBC Chicago.

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Prosecutors said Walsh had become “very invested” in Clancy’s nationally watched trial and was discussing it with friends until about 12.30pm that day. A neighbor found Barrett less than four hours later.

Walsh was found elsewhere in the home with injuries authorities said were self-inflicted.

Prosecutors said she later told investigators that she killed her son because she believed he was the “devil” and the “anti-Christ.”

Her attorney, Andrea Lyon, told reporters Walsh was experiencing a psychotic episode and called the boy’s death a tragedy for the entire family.

Illinois mother Corie Walsh is accused of killing her son just hours after texting friends about Lindsay Clancy’s high-profile child murder trial. Credit: Will County Sheriff’s Office

Police were called to Walsh’s home in Frankfort, about 56km southwest of Chicago, shortly before 4pm after a neighbor discovered Barrett in the basement, according to prosecutors’ petition seeking to keep Walsh jailed before trial.

The neighbor found the boy and began CPR while calling 911, prosecutors said. He was taken to a hospital, where he was pronounced dead.

An autopsy determined that he died from asphyxia caused by ligature compression of the neck.

Police searching the house found Walsh fully dressed in a bathtub containing bloody water, prosecutors said.

She had cuts to her wrists and thighs and was taken to a hospital with injuries authorities described as not life-threatening.

The disclosure that Walsh had been following Clancy’s trial came days after a Massachusetts judge declared a mistrial in that case when jurors said they could not reach a unanimous verdict.

Police allege Walsh became ‘very invested’ in Clancy’s trial, during which Clancy argued she killed her own three children while suffering from postpartum psychosis. Credit: AP

Clancy, a former labor and delivery nurse, was accused of killing her three young children in 2023.

Her lawyers argued that she was legally insane and suffering from postpartum psychosis. Prosecutors maintained that Clancy understood what she was doing and knew it was wrong.

Authorities in Illinois have not alleged that Clancy’s trial played a role in the killing of Walsh’s son, and no evidence made public so far establishes a connection beyond her discussion of the case.

Frankfort Police and prosecutors in Will County did not respond to calls for comment on Monday.