Kesia Grant, 24, pleaded guilty to Homicide by Child Abuse in the January 2011 death of her 3-year-old cousin, Tylashia Grant.
Kesia Grant was sentenced to 27 years in prison.
Tylashia died from burns on her body and toxic effects of pain medications in her system, which caused complications of the third degree burns.
The child lived with Grant at a home on Badger Lane in Florence County.
Kesia Grant's mother, Jeraldine Brockington, 43, had custody of Tylasia. Brockington is also charged in the child's death and is awaiting trial.
Kesia Grant cried throughout the sentencing and admitted to the judge she was guilty in Tylashia's death. She explained how she had instructed her 6-year-old son to boil a cup of water in the microwave. She then poured the scalding water in Tylashia's diaper to teach her a lesson about wetting her pants.
The child suffered through excruciating pain for more than a week until she was taken to the hospital. She had already died by the time she arrived.
The child's preschool teacher at Carver Elementary School, Megan Johnson, cried as she told the judge how much Tylashia meant to her classmates. Johnson said they called her "Little Bit" because she was so small at just 36 inches tall and 26 pounds.
Johnson told the court Tylashia will forever live in their hearts.
Grant is not eligible for parole and will have to serve her entire 27 year prison sentence.