A Green Country teenager has been charged with his sister's murder.
Devin Stanley, 19, is being held in the Osage County Jail.
Investigators believe he stabbed his sister, 16-year-old Larisa Fraley, this week.
Her body was found in a van in a rural part of Osage County on Tuesday.
Detectives said they also have connected Stanley to his 71-year-old great-grandmother's murder.
Esther Driskell was discovered stabbed in the Skiatook home she shared with both teenagers.
Stanley is being held without bond.