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A man accused of decapitating his 4-year-old daughter battled paranoid schizophrenia a decade before the killing, his sister said.

John Patrick Violette, 37, of Clayton, has been charged with murder for the Jan. 12 death of his daughter, Katlin. Denise Violette said her brother was diagnosed with schizophrenia in the mid-1990s at a mental hospital in California.

"I look back and I think, 'We should have never let him out of that place,"' Denise Violette told The News & Observer of Raleigh.

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Schizophrenia is a brain disorder that often causes victims to hear and see things that aren't there. It can sometimes go dormant only to erupt in dramatic breaks with reality, mental health experts say.

John Violette's illness appeared to have subsided, and he moved to North Carolina to live with relatives. He soon met Amber Marks at church and the two were married nearly eight years ago. It's unclear whether Violette's wife knew of his past with schizophrenia.

Violette's lawyer, Robert Denning, has asked a judge to send his client to the Dorothea Dix state mental hospital where psychiatrists could determined whether he is competent to stand trial.

"He doesn't seem to grasp what's going on," Denning said.

Violette's wife, Amber, found their daughter dead at the couple's suburban home in Clayton, about 15 miles southeast of Raleigh. Authorities arrested her husband at a hotel room in Washington, D.C., early the next morning.

Growing up, John Violette and his sisters moved several times because their father was in the military. The family settled in California, where their parents separated.

He experimented with drugs, which Denise Violette thought were the source of her brother's mental breakdown. "I thought it all had to do with the bad choices he made," she said.

When she visited her brother at his home in Hawaii, he told her that men were following him, Denise Violette said. She said she convinced him to come back to California, where his behavior became panicked.

John Violette would hide from people he imagined might be following him and even tried jumping from his brother-in-law's moving car, his sister said.

He was later diagnosed with paranoid schizophrenia and was put on medication, which he eventually stopped taking, Denise Violette said.

Years later, after restarting his life in North Carolina, John Violette was loving family life. He and his wife met for lunch at their house each day, and the family would set up tents and sleeping bags in the living room for slumber parties, Denise Violette said.

Then tragedy struck, and the ordeal has been a nightmare for the family, Denise Violette said.

"Even now, I think I will wake up and this will be someone else's family," she said. "It is so beyond understanding."

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