Updated

A 15-year-old western Michigan boy faces a detention hearing in the stabbing of his 13-year-old sister in their Caledonia Township home.

The Grand Rapids Press reports that the teen is due Monday in Kent County Juvenile Court.

Sheriff's deputies found the girl with multiple stab wounds about 1 p.m. Saturday after her 15-year-old brother called 911. She was taken by an emergency helicopter to a Grand Rapids hospital. Authorities have not yet released her condition.

Her brother was arrested Saturday at their home, southeast of Grand Rapids. Their names haven't been released.

WOOD-TV reports that their father was at work at the time of the stabbing.

A prayer vigil was held Sunday outside Caledonia High School's football stadium for the 13-year-old girl. Both siblings attend schools in the district.