The 6-year-old brother of Marchella Pierce is expected to take the stand Thursday in his sister's murder trial.

Pierce was found dead in September 2010. Prosecutors say she was tied to her bed, beaten, drugged and starved. At her death, prosecutors say her stomach contained one kernel of corn. Her mother, Carlotta Brett-Pierce, and grandmother, Loretta Brett, have pleaded not guilty in her death.

On Tuesday, jurors saw a series of crime scene photos depicting the bed, roped tied to the bed that prosecutors say was used to tie the girl down. Photos of the dead girl show black-and-blue bruises on her face, arms, and back. Practically every rib was visible through her skin.

Jurors were again shown photos Wednesday, this time of the girl's dramatic weight loss before she died. 

Brett-Pierce's attorney has said the woman was a good mother. Brett's attorney said the grandmother was a caregiver and had tried to raise the children in the home, and didn't know about the abuse. Two juries are hearing the case.

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