The Fresno Police Department was initially told that 61-year-old Patty Kennett was missing on November 15.
Kennett's family was told that she died from injuries while doing yard work, but her family was not able to locate her body at any hospital.
There were also no reports of calls for emergency services after her injury.
Homicide detectives took over the investigation and served a search warrant at 54-year-old Lisa Hinthorne's home, who is Kennett's half-sister and who she was last seen with.
Detectives found evidence that suggested there was foul play in Kennett's death while at the home.
Hinthorne and 33-year-old Glenn Howard were named suspects in Kennett's death.
Authorities found Kennett's car in Madera with blood in the trunk on November 18.
Her body was found in Coalinga.
Kennett's death was ruled a homicide, and both Howard and Hinthorne were taken into custody.