WXIA-TV reports the shooting victims have been identified as 85-year-old Edith Renner, 49-year-old Suzanne Renner and 45-year-old Charles Renner IV.
Authorities say one of the victims' co-workers was concerned when one of the victims didn't show up to work. Police say the unidentified person found the bodies inside a house on Brandon Ridge Drive Wednesday afternoon.
Officials say a pistol was lying near Charles Renner's body.
Sandy Springs is just north of Atlanta.