WAUTOMA - The mother of a 6-year-old girl killed and a 4-year-old girl injured in February while getting on a school bus near Plainfield has filed a lawsuit against the driver who hit the girls.

Carl L. Mullenix, 76, of Plainfield, was driving on the shoulder of State 73, about a half mile north of Waushara County AJ, in the town of Oasis, when he hit Maryana Kranz and her younger sister as they were getting on the bus for school at 7:15 a.m. Feb. 10, according to the Waushara County Sheriff's Office.

On Wednesday, Benjamin Welch, an attorney representing the girls' mother, Shannon Kranz, filed a wrongful death lawsuit against Mullenix, according to online court records.

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Maryana's 4-year-old sister suffered a concussion during the crash, her mother told the Stevens Point Journal in February.

Shannon Kranz said her daughter would make sure others were OK before she took care of herself. Maryana loved to dance and listen to music. She loved all things bright and colorful, her mother said.

The Waushara County District Attorney's Office did not file charges against Mullenix following the crash.

This story will be updated.