Sherry Marino wants to determine if the body buried at Queen of Heaven Cemetery in Hillside for more than 30 years is actually her son, Michael. The remains were not publicly identified as belonging to the boy until four years after his 1976 disappearance.
Marino's attorney, Robert Stephenson, said he filed the exhumation request after dental records raised questions about the identity of the remains buried at the cemetery.
"She told me today that she always asks the same question, 'Is this really you?'" Stephenson said. "Since we have the ability to determine that definitively, and we have serious questions... Ms. Marino is entitled to those answers."
After Gacy was arrested in 1978, police found 29 bodies of boys and men on his property. There were 33 victims in all.
Gacy was executed in 1994.