Their mother was killed by their father just over a year ago. She was stabbed to death when a psychotic break triggered by his post-traumatic stress disorder put him in a delusional war zone in which she was part of an offensive launched against him.

On Wednesday, the adult children of the Laotian immigrant couple begged for mercy for their dad. Their father snapped in a panic and slaughtered his wife of more than 40 years.

What he got was the promise made to him last month in a plea bargain: a 16 years-to-life term on his admission to one count of second-degree murder.

The deal also included an agreement that defendant Sy Choy Saeteurn, 66, would spend at least the first seven years of his term in a state mental hospital on a finding that he was not guilty by reason of insanity on a second count of endangering his 10-year-old daughter, who witnessed the killing of her mother.

The children of Saeteurn and his 60-year-old wife, Muang Saeteurn, were conflicted in their statements to the court. They appealed to Sacramento Superior Court Judge John P. Winn to balance their grief over the loss of their slain mother against their love for the troubled father who killed her.

"Speaking on behalf of my mother, she would say if it were only between her and my father, she would probably have no mercy," the couple's 36-year-old daughter said in a letter to the court read by Deputy District Attorney Scott Triplett. "She placed her life and her trust in the man ... yet died a very violent death at his hands.

"But she would ask the court for mercy because the desire to minimize our pain and suffering supersedes her quest for vengeance

"She knows ... we will not abandon him because she has taught us to have love and compassion," the daughter wrote. A schoolteacher, the daughter asked that her name not be published because she doesn't want her students to know about her ordeal.

She said her father expressed his sorrow to "all those who are impacted by his insane act."

The judge called the case a tragedy and imposed the sentence he worked out with Triplett and Assistant Public Defender Sue Karlton when Saeteurn entered his dual plea Nov. 30 to the second-degree murder and child-endangerment charges.

Sheriff's deputies arrested Saeteurn on Dec. 8, 2010, after the young daughter broke out of their home on Pinot Noir Way in the Vintage Park Drive area of unincorporated south Sacramento and told a neighbor her father had killed her mother.

A psychiatric examination diagnosed Saeteurn with major depression disorder with severe psychotic features and post-traumatic stress disorder with delayed onset, according to the defendant's probation report. His older daughter identified him in the report as a veteran of the Laotian military who fought in the wars of Southeast Asia from 1968 to 1972.

She said her father suffered a panic attack and stabbed his wife several days after "someone dressed in a uniform" came to the parents' house "and startled her father," according to the probation report.

Karlton said the person in the uniform was a mailman who he believed was a soldier.

"He thought they were coming to get him and he reacted," the defense lawyer said. Saeteurn turned on his wife in the aftermath of the visit from the mailman "thinking she was a soldier and somebody was coming to get him," Karlton said. "It's just tragic."

The probation report said Saeteurn was unemployed at the time of the attack but was still receiving a monthly income of $1,400.

It said he drank alcohol regularly and chewed opium pretty much every night for the past 21 years "to help him feel better."

Saeteurn's probation report quoted his psychiatrist, Dr. Christopher S. Wadsworth, as saying the defendant had responded well to treatment that included antidepressant medication.

Wadsworth said Saeteurn thought his actions in killing his wife were "morally justified and that he was acting in self-defense," according to the probation report.

The daughter also had been targeted for death but escaped by jumping out of a bedroom window. She has since been placed with another family, the probation report said. It quoted the girl's Child Protective Services caseworker as saying she has adjusted well.

"I used to be mad at my dad, but now I just want him to be OK and taken care of," the girl, now 11, was quoted as saying in the report. The girl said her mother is "with us in spirit" and "I think she wants all of us to be happy and move on with our lives."

The older sister said, "We ask for the court's mercy for my father and ask my mother for forgiveness."

"We hope he will one day regain his sanity and come home to his family," she said.

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