The Rock County Sheriff’s Office is investigating the death of an elderly woman.  Deputies were called to the 11000 block of West Mineral Point Road about 5:30 a.m. Monday and found the woman dead in the garage.  Officials say a caller to 911 had stopped by the home to check on the welfare of the woman and informed emergency dispatch another person was in the home and unaware of the call.  The other subject was taken into custody as a person of interest.  Officials describe the incident as a complex violent death investigation.  Investigators say the deceased, caller, and person of interested are all related and this is considered an isolated incident with no on going threat to the community.