Acosta,54, another former DCFS employee, Andrew Polovin, 48, are accused of allowing AJ to be placed in a dangerous situation.
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AJ Freund murder: JoAnn Cunningham makes tearful address during first sentencing hearing
Polovin appeared in court last week, where he pleaded not guilty.
A lawsuit filed on behalf of AJ Freund's estate accuses these men of failing to fully investigate allegations of abuse against AJ.
The Crystal Lake boy was found dead in a shallow grave not far from his parent's home last year. The horrifying child abuse case sparking outrage in the community and calls for DCFS to be held accountable.
RELATED: Crystal Lake home of murdered boy demolished
Home of murdered Crystal Lake boy AJ Freund demolished
AJ's mother, JoAnn Cunningham, pleaded guilty last December to AJ's murder. In July, she was sentenced to 35 years in prison.
Last week, his father Andrew Freund pleaded guilty and was sentenced to 30 years in prison.