Published: May 07, 2014 10:41 AM EDT

TAMPA, Fla. (AP) - The trial of a Tampa mother accused of killing her two teenagers has started late because she reported a medical problem.
    
Julie Schenecker told her attorneys Wednesday that she was having numbness in her legs. The court doctor evaluated her, and she returned to the courtroom about 90 minutes late.
    
Schenecker is charged with two counts of first-degree murder. Prosecutors say she killed her 16-year-old daughter and 13-year-old son.
    
Her ex-husband testified for the prosecution Tuesday. The two divorced after the killings.
    
Parker Schenecker said he had not been concerned for their children's safety when leaving them in his wife's care.
    
Julie Schenecker has pleaded not guilty by reason of insanity. Her attorneys say she has suffered from bipolar disorder and depression for decades.
    
Prosecutors say the slayings were premeditated.

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