Billy Bob Thornton's 32-year-old daughter Amanda Brumfield has been found guilty of aggravated manlaughter for the death of 1-year-old girl in 2008.
Prosecutors have said that Brumfield was convicted last Friday, E! Online reported.
Brumfied was accused of killing her bestfriend's daughter Olivia Madison Garcia while babysitting her in 2008.
Brumfield in her defence had said that the child fell from her playpen while trying to climb out of it. The defence had argued that the fall could've aggravated some previous injury.
Meanwhile, the prosecutors retaliated by saying that it is "impossible" for a child to get a 3.5-inch fracture followed by bleeding and swelling around the brain from a fall from her height.
Brumfield was earlier acquitted of first-degree murder and aggravated child-abuse charges.