CHICAGO (AP) — The estate of the 5-year-old northern Illinois boy who was beaten to death and buried in a shallow grave this year has filed a lawsuit contending that two state child welfare workers ignored clear signs that the boy was being abused months before his death.

The federal lawsuit filed Wednesday asserts that Department of Child and Family Services worker Carlos Acosta and his supervisor, Andrew R. Polovin, either didn’t investigate allegations that Andrew “AJ” Freund had been abused or found such allegations unfounded despite concerns about the boy raised by police and others.

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In April, AJ’s body was found buried near his family’s Crystal Lake home. His parents, Andrew Freund and Joann Cunningham, were charged with first-degree murder in his death.

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Acosta didn’t immediately respond to a request for comment and no listed phone number could be found for Polovin. The child welfare agency isn’t named as a defendant in the lawsuit.

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