An account in Cass County, Michigan

My late Aunt once told me a story that may be of interest to you. In the late 60's she and her sisters were summer camp horse instructors for camp Bellowood of Union, Michigan in Cass County. My aunt was riding late one evening and notice that the horse seem to be really spooked about something. She was having difficulty controlling the animal so she just let it run on its own. While the horse was running she looked to her side and observed a large white colored figure that was keeping place with the horse for a short time. The figure was close to her height on a mounted horse. She was understandable spooked herself for some hours afterward.