The Northwest Herald reports that Joann Cunningham gave birth to a girl on May 31.
The baby is being held in protective custody while both Cunningham and her ex-boyfriend Andrew Freund Sr. are being held in connection with AJ Freund's disappearance and death.
Cunningham, was charged with five counts of first-degree murder, four counts of aggravated battery, two counts of aggravated domestic battery, and one count of failure to report a missing or child death.
Andrew Freund Sr. was charged with five counts of first-degree murder, two counts of aggravated battery, one count of aggravated domestic battery, two counts of concealment of a homicidal death, and one count of failure to report a missing or child death.
The charges came days after Cunningham, who is seven months pregnant, made a plea for AJ's return to ABC News.
"I just want my kids, that's all I have. Those are my life, my kids," Cunningham said.
The boy was found six days after he was reported missing in a shallow grave, wrapped in plastic, Crystal Lake Police Department Chief Jim Black said Wednesday afternoon.
Police say the two killed the 5-year-old boy in their Crystal Lake home and then buried his body at a site in Woodstock.
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