Billy Bob Thornton’s estranged daughter Amanda Brumfield was sentenced to 20 years in prison Thursday after she was found guilty of aggravated manslaughter of a child in May.

Brumfield, 32, was found guilty in connection with the 2008 death of her best friend’s daughter, 1-year-old Olivia Madison Garcia, who she claimed hit her head after falling while trying to climb out of a playpen.

During the trial prosecutors argued that it was “impossible” that the three-and-a-half inch fracture on Garcia’s skull was caused by a fall from that height.

A source close to Brumfield told RadarOnline.com that her defense team plans to file an appeal of the sentence.

Billy Bob Thornton’s estranged daughter Amanda Brumfield was found guilty of aggravated manslaughter of a child in May, and RadarOnline.com has exclusively learned that a judge denied her request for a new trial and she will be sentenced for the crime on October 6.

Judge Reginald Whitehead issued his order on August 29, writing: “Defendant’s motion for a new trial is denied.”  Brumfield, 32, faces up to 30 years in prison at her sentencing.

A source close to Brumfield told RadarOnline.com that her defense team plans to file an appeal immediately following sentencing.

Amanda Brumfield, the estranged daughter of Billy Bob Thornton, was found guilty of aggravated manslaughter of a child in May, but RadarOnline.com has exclusively learned that she may get a new trial.

Her defense attorney Jamie Kane asked Judge Reginald Whitehead for a new trial in a hearing Thursday morning and the judge ruled that he would take it under consideration and release his decision at a later date.

Kane exclusively told RadarOnline.com that Brumfield, 32, “is anxious to have this verdict set aside and get a new trial because she is innocent.”

Amanda Brumfield, the estranged daughter of Sling Blade star Billy Bob Thornton, has been found guilty of aggravated manslaughter of a child.

In addition, Brumfield, 32, was found not guilty on first degree murder and aggravated child abuse charges in connection with the 2008 death of her best friend’s daughter, 1-year-old Olivia Madison Garcia.

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