The 1-year-old was pronounced dead shortly after arriving at the Monroe Carrel Jr.
The girl's adoptive father reportedly forgot that the girl was left in the auto at the East Nashville home after dropping her sibling at a daycare centre.
He apparently forgot about the girl and drove home, where she was left in a vehicle seat.
Her birth mother, who was not publicly identified by NewsChannel 5, told the station that she learned about the toddler's death Wednesday night when the adoption agency informed her that there had been a bad accident. She was rushed to Vanderbilt Hospital and pronounced dead.
Authorities say the parents had recently adopted Katera.
The investigation is ongoing.More news: Weinstein, infamous face of the #MeToo movement, now faces the public
More news: Trump charges Naval Academy graduates with mission of victory
More news: Nipah virus claims one more life, Death toll rises to 11
A one-year-old girl has died after being left in a hot pick-up truck.
The mother, Jenny Barker, later drove to the daycare to collect her children. It was unclear whether the adoptive father would face charges. His wife left for work in her own vehicle.
According to NewsChannel5, Wednesday's high was 89 degrees, so "the interior of the truck could've easily reached between 130-170 degrees".
Matt Barker flew back to Nashville, arriving late Wednesday, police said.
Authorities in the state have previously issued advice to parents, after it was found that Tennessee is in the US's top 10 states for child deaths in hot cars.
According to the Metro police, the dad "forgot about the child" after dropping off her sibling.