PLYMOUTH TOWNSHIP, Mich. (AP) — A judge has ordered an exam to determine whether a 15-year-old Detroit-area girl is competent for trial on charges she plotted with her boyfriend to kill her family.

The prosecutor’s request for the evaluation was granted Friday. The hearing and preliminary examination have been scheduled for Dec. 12.

The girl and 23-year-old Michael Rivera are charged with assault with intent to murder and conspiracy to commit murder.

The girl is charged as an adult. Her parents said she and Rivera were in a sexual relationship.

The Associated Press isn’t naming her or family members because prosecutors have said they may file sex charges against Rivera.

Prosecutors say she stabbed her brother Oct. 17 in their Plymouth Township home. They contend Rivera was outside the house sending text messages instructing her.

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