The younger brother was removed from the home by DCFS following AJ's disappearance.
Andrew Freund Sr. and Joann Cunningham are charged with first degree murder in the death of their son AJ.
WATCH: AJ Freund's body found 6 days after he was reported missing
Cunningham gave birth to a baby girl in jail in May. The baby is being held in protective custody. A separate hearing regarding a paternity test for the baby will also take place Monday.
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.
WATCH: DCFS timeline of interactions with AJ Freund's family
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 boy was found in a shallow grave, wrapped in plastic six days after he was reported missing last April, police said.
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