The 4-year-old boy who was hospitalized Sunday night after ingesting an unknown amount of gasoline also tested positive for cocaine in his system, according to the Dane County Sheriff's Department.
His 2-year-old sister, who also ingested gasoline, died at a local hospital emergency room shortly after the incident Sunday in the Town of Medina.
Court documents indicate that not only did the children ingest gasoline, at least one of them has done it before.
Neighbor Bob Dunn said he was shocked to hear the new details.
"Unbelievable. I found that kind of hard to believe," Dunn said.
Detectives conducted a search warrant at the site of the incident on Tuesday. Authorities said they have uncovered supplies for drug dealing, possible drug paraphernalia, multiple cellphones and more. The same court records show when the 4-year-old boy was treated for gas ingestion, a presumptive blood test on the boy found a positive result for the presence of cocaine in his system.
"Those tests can produce false positives, so we do need to send that off to a lab for more conclusive results, which could take four to six weeks," said Elise Schaffer, spokeswoman for the Dane County Sheriff's Office.
Investigators said they are trying to determine whether illegal drugs played a role in Sunday's incident.
The children's aunt told investigators that she, the children's mother and others have smoked crack several times in front of the children, with the last time in January, according to the court documents.
Investigators said the boy had ingested gasoline in the past and was warned to stop. His mother even went as far as searching online for treatment for gas ingestion, according to court documents.
The mother last lived in Portage, according to court records. Neighbors there said it's been four years, but they remembered her and said she used drugs regularly.
But in the Town of Medina, where the mother had been staying up until Sunday, neighbor Dunn said he's shocked.
"She has always taken care of those kids. Those kids are very well fed. She always bought plenty of diapers," Dunn said.
While the mother hasn't yet been charged in the case, sheriff's officials said charges could come. They said it will depend on when test results come back. Autopsy and toxicology results on the girl who died are also still pending.
The Dane County Sheriff's Office said the boy has been put into foster care.