Miller's father, Donald Flowers, was killed last March in Minot, North Dakota while working for Halliburton.
Flowers and 33-year-old Charles Davis, of Trinity, Texas, were working together in a conference room at a local hotel.
According to Flowers' family, a cell phone started ringing and that's when they said Davis, a former marine, snapped.
Davis is accused of stabbing Flowers in the neck, but the attack didn't stop there.
"He left the room, he came back, and he stabbed him again," said Paula Villarreal, Flowers' sister, "and he kept saying, 'those damn androids, damn droid, damn droid'."
Earlier this week, a judge in North Dakota accepted doctors' evaluations that Davis was not responsible for his actions due to a lack of criminal responsibility, similar to a temporary insanity plea.
"[Davis]left the room, and went back in and stabbed [Flowers] more times," said Destiney, "How are you going to say you didn't know what you were doing?"
Flowers' family said they were told Davis suffers from PTSD after his time in the Marines.
Villarreal said if that's true, then Davis isn't the only one to blame.
"I feel like our country has let down our service people, and they're not giving them the help they need," explained Villarreal.
Villarreal also said the two men's employer, Haliburton, should have done more to help Davis.
"I blame Haliburton," said Villarreal, "I blame Haliburton 75% for this. I blame our country, but Haliburton knew the circumstances that were happening. Everyone was telling them."
While they admit nothing will bring back the man they loved; the man who they said just wanted to come home and spend time with his future fishing buddy, the family of Donald Flowers said they will honor his memory by sharing his legacy with the grand-kids he barely knew."
"It's very hurtful, very hurtful that this guy is getting off for this," said Shirley Flowers, Donald's sister, "So I hope the Lord really punishes him for what he's done to our family."
Reporter's Notes by Ryan Robertson:
Flowers' family said Charles Davis will be admitted to a state mental hospital on May 1st.
After 90 days, the judge in the case will decide whether Davis should stay in a mental institution, or possibly be released.
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