Police responded to the home of Brenda Bowers, just north of Butlerville, on Saturday morning around 11 a.m.
Bowers found a 28-year-old man in the bedroom of her 16-year-old granddaughter, police said.
When Bowers allegedly confronted the man with a handgun the firearm discharged striking the man in the right ankle. The man identified as Daniel Sidwell, of Bartholomew County, was taken to an Indianapolis hospital for treatment.
Bowers has not been charged but the incident remains under investigation.