Among those shocked was Hinthorne's ex-wife, Terrie Fairley.
"Patty was her ride and die. Patty was everything to her," said Fairley. "So, I don't understand what happened."
Fairley and Hinthorne were married for 32 years and said Hinthorne used to be a loving and caring person before abruptly moving out in July and asking for a divorce.
After that, Fairley said Hinthorne started spending more time with her sister Patty and moved in with her friend, Glenn Howard, Jr. Howard, Jr. is also facing charges in the case.
The last time Fairley says she spoke to her ex was a week ago.
"She was kind of numb, no emotion," said Fairley. "I don't even know why she calls me."
That phone call was just days after police say Hinthorne shot and killed her half-sister.
Fairley said she grew suspicious when Hinthorne started telling people her half-sister was dead in mid-November, but there was no body or any trace of Kennett. Kennett's family members reported her missing on November 15th.
"The information that was received was that Patty fell victim as the result of an accident with some type of industrial equipment, and the ambulance was called," said Lt. Paul Cervantes, Fresno Police. "Ambulance personnel never responded to this location, and very quickly, it became apparent that Patty was a victim of foul play."
Police said after interviewing Hinthorne, they searched her home.
During their search, it was discovered that Hinthorne had a surveillance camera that investigators say reveals part of the crime.
"What the video does depict, though, clearly, is that our victim falls to the ground, and at some point later on during the evening, Lisa and Glenn are both observed removing the victim's body," said Cervantes.
Authorities found Kennett's car in Madera with blood in the trunk on November 18, but Howard is accused of driving Kennett's body to a remote area of Coalinga off Highway 198, where it was later found.
"She did what she did, and it was a horrible way for Patty to die. She didn't deserve that, and I hope justice gets served," said Fairley.
Hinthorne also has an open, unrelated domestic violence investigation and restraining order case against her.
Hinthorne is being held on a $1.5 million bail and will be arraigned Wednesday on a murder charge with a gun enhancement.
Howard is set to be arraigned next week on an accessory to murder charge.
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