Elzbieta Plackowska, Illinois mom, accused of fatally stabbing her son and another child

(CBS) NAPERVILLE, Ill. - A mother who was baby sitting is due in court Thursday to face charges that she killed two children under her care in a suburban Chicago home, CBS Chicago reports.

Elzbieta Plackowska, 40, was charged with first-degree murder in the stabbing deaths of two children at a Naperville home on Tuesday night. 

On Wednesday, Naperville police questioned Plackowska, who was reportedly behaving erratically just before authorities believe she fatally stabbed her 7-year-old son and a 5-year-old girl she was babysitting at the girl's home.

Two dogs were also found dead inside the home.

Plackowska has reportedly been arguing with her husband after her father had recently died in Poland, and she wanted to return there. 

According to the Daily Herald, police found the children after being called to do a well-check on the home. Sources tell the paper that Plackowska was not at the home at the time, but that she was apprehended soon after and was "covered in blood."

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