Two persons are charged for the death of an 18-month-old girl on Christmas Day after autopsy showed it was because of fentanyl overdose.

Authorities said the body of Ava Floyd, child of couple Antonio Floyd and Shantanice Barksdale, had "extraordinary" amount of the substance. What's more harrowing is that the baby had enough of the synthetic opioid to kill "several adults."

High Amount Of Fentanyl In The System

According to Macomb County Prosecutor Eric Smith, autopsy showed that the baby had taken about five to 15 times of the amount of fentanyl the authorities had ever seen in the recent 30 overdose deaths. The case was also the highest level of the substance in the system the medical examiner's office had ever seen.

The parents were charged with second-degree murder on Monday, putting them behind bars without bond. Smith believed the toddler had ingested the fentanyl by drinking the synthetic opioid.

Antonio Floyd and Barksdale, along with their three children, were at home on Christmas morning and went to Warren, Michigan to visit their grandmother by the afternoon. Shortly after, the toddler suddenly stopped breathing and was rushed to the hospital where she was pronounced dead.

There were no physical signs that Ava was abused, hospital staff said in press release. However, a sibling of the toddler allegedly told the parents that the baby ingested fentanyl.

Manufacturing Fentanyl

After securing a search warrant in the home of the couple and the grandmother, authorities saw guns, drug residues, and scales, among many others that made them believe that the couple are producing and packing fentanyl in their house for distribution.

"[T]o see an infant experience such a tragic death on Christmas morning as a result of ingesting a large quantity of her parents' fentanyl is truly gut-wrenching," the prosecutor said.

The couple's children are overseen by the Michigan Department of Health and Human Services. The accused are also charged with felony firearm offenses, manufacturing of controlled substance, and manslaughter on top of second-degree murder.