I am trying to find more information on a murder case my grandfather may have been the culprit of.

I had gifted my mom a DNA test kit around Christmas. At the time she had told me she was always scared of taking one because she had always suspected her father of a r*pe and murder of a young girl in Teton Valley in Idaho. I believe it was sometime from 1985-2000, and I am also aware that he had committed previous acts against young girls, however I don't know their ages. I remember never being allowed to be alone with him. If this doesn't belong here, please let me know and point me to someplace this belongs.