A one-year-old child was found dead in his car seat in a house after drying due to starvation after a Tennessee mom died of a fentanyl overdose.

Meanwhile, the toddler's three-year-old sister was found alive. The girl was trying to feed her brother for days, according to a KETV report.

The bodies of Tiffany Spears, 32, and her toddler son, Nicholas Crowder, were found in February at their home in Portland.

The boy had been strapped into a car seat that was left on a bedroom floor.

The autopsy found that Spears died of a drug overdose combining fentanyl and methamphetamine. Her and her son's deaths have been ruled accidental.

READ MORE: Colombian Woman Found Partially Eaten by Her Cats After She Died From COVID at Her Flat In Spain

The Investigation

The Tennessee Chief Medical Examiner reported that the pair were found dead on February 9 in their home in Portland.

A probation officer conducted a follow-up visit to the home that day and found that the front door was locked and Spears was lying on the ground.

The toddler was nearby in a car seat, while the three-year-old girl was running around inside the home, according to a People report.

The autopsy also stated that drug paraphernalia was found inside the home with Crowder strapped into a car seat with no access to food, water, or care.

Spears had not been seen since February 5 before her body was discovered.

Major Tim Bailey with Sumner County Sheriff's Office said that it takes a toll having to investigate these types of cases, but they try to push through and find out all the answers that they can.

Bailey said that they are also trying to create a timeline of events to determine when was the last known contact that was made with Spears, according to a WSMV report.

Meanwhile, the three-year-old child was released to other family members.

The sheriff's office said that there have been other separate cases of deaths at the same rental homes. They added that those deaths were also drug-related.

Drug Overdose

About 0.5 million deaths around the world are attributed to drug use, with more than 70 percent of these deaths related to opioids and more than 30 percent of those are caused by overdose, according to the World Health Organization 2020 fact sheet.

Around 115,000 people died of opioid overdose in 2017.

In the United States, the number of people dying from opioid overdose increased by 120 percent between 2010 and 2018, while two-thirds of opioid-related overdose deaths in 2018 in the U.S. include fentanyl and other similar drugs.

Fentanyl is a strong synthetic opioid that is used as a pain reliever and as an anesthetic. The said drug is also 50 to 100 times more potent than morphine.

Fentanyl and its other chemically similar drugs have been related with a spoke in deaths from an opioid overdose.

There have also been reports that drug dealers may be adding fentanyl to their products to increase the potency of the drug. Many users who test positive for fentanyl use do not realize they took the drug substance.

READ NEXT: Scott Peterson Is off Death Row and Laci Peterson's Family Is Devastated

WATCH: Drug overdoses: The hidden epidemic in the pandemic - from PBS NewsHour