A Brooklyn jury found Loretta Brett guilty Friday of the most serious charges in the death of her 4-year-old granddaughter, Marchella.
The verdict came two days after Marchella's mother, Carlotta Brett-Pierce, was convicted of murder. She faces life in prison when she is sentenced June 6.
Prosecutors said the little girl weighed about half what a healthy 4-year-old should. When she was found in September 2010 she had been tied to her bed and was beaten and had dozens of adult doses of Claritin and Benadryl in her system.
Brett faces up to 25 years in prison.
Her lawyer says she plans to appeal.
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