A 1-year-old girl was found dead late Wednesday inside a home in a suburban neighborhood near Chicago, WLS-TV reported.
Sheri Gordon, the mother of missing toddler Semaj Crosby, is now under investigation for an allegation of neglect, the Department of Child and Family Services confirmed.
Ackerson said Semaj's body was found after the mother's lawyer gave the sheriff's office consent for the house to be searched Wednesday night.
Semaj ML Crosby was last seen by her mother about 6:30 p.m.in the front yard of her residence near Luana Road and Richards Street in unincorporated Joliet Township, according to the Will County sheriff's office.
An autopsy is planned Thursday to determine cause of death.
Ackerson called Semaj's death suspicious, but not necessarily a homicide.
"We have had prior contact with this family including four unfounded investigations for neglect and two prior pending investigation for neglect opened in March 2017", DCFS spokeswoman Veronica Resa said in the email.
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"She was right there one minute and gone the next", Ackerson said.
The Will County Sheriff's Office considers this to be a missing child case, and Semaj's family is fully cooperating with detectives, Ackerson said. Final results will depend on toxicology results and the police investigation.
Ackerson said that between five and fifteen people were living in the house at various times.
The child was last seen wearing a gray long-sleeved shirt with a cat face on it, and dark jeans.
Will County Deputy Chief Rick Ackerson speaks to the media Wednesday during a press conference about the disappearance of 1-year-old Semaj Crosby in Joliet.
NBC 5 learned Wednesday that Gordon had hired an attorney as search crews were continuing their efforts to find Semaj.
"It just hurts me, because it shouldn't have happened at all", he said. And, he said, based on statements from credible witnesses who saw the girl outside the house shortly before she vanished, authorities believed the girl was not inside. Ackerman said a family attorney referred to them as "squatters".