Chicago (CNN) -- Actress and singer Jennifer Hudson testified Monday in the trial of a man accused of killing her mother, brother and 7-year-old nephew. She broke down in tears several times on the stand as she remembered her family. Hudson was the prosecution's first witness. She identified the defendant, William Balfour, the estranged husband of her sister, Julia. "None of us wanted her to marry him," she said. "We did not like how he treated her." Hudson, dressed in black, also testified about her relationship with her mother, saying she spoke with her mom every day and slept in the same bed with her until she was 16.
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Hudson's sister, Julia, testifies defendant threatened to kill her family
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"Where he was, I tried not to be," Jennifer Hudson says of William Balfour
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Balfour is accused of fatally shooting Hudson's mother, brother and nephew
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Balfour, the estranged husband of Hudson's sister, has denied the charges
@placeholder was detained for questioning the day after the victims were found at the Chicago home.
Prosecutors have portrayed @placeholder as a jealous man who murdered three people in a rage at the thought that his wife had a boyfriend.