Sister, 3, tried to feed baby brother eggs to survive after mum's fatal drug overdose

Mum Tiffany Spears and her 15-month-old son Nicholas were found deceased inside a Tennessee home. Photo / Facebook

WARNING: This story contains distressing content

Autopsies in Tennessee show that a 1-year-old child starved to death in his car seat in a house where his mother died of a drug overdose, while his 3-year-old sister, found alive, had tried for days to feed her brother.

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

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

The autopsy results released Monday showed that the woman had been dead for several days when a probation officer making a home visit alerted the Sumner County Sheriff's Office, officials said.

Tests showed her cause of death to be drug toxicity from methamphetamine and fentanyl, news outlets reported.

Mum Tiffany Spears and her 15-month-old son Nicholas were found deceased inside a Tennessee home. Photo / Facebook

The 15-month-old boy died of starvation and dehydration, despite his bigger sister's attempts to feed him with eggs and other food.

Eggshells and dried eggs were found in and around the car seat.

Both deaths were ruled accidental.

The 3-year-old was treated at a hospital as a precautionary measure.

"It appeared the decedent's sister tried to take care of the decedent for several days," the autopsy report said, noting that food was found in and around the car seat.