LOS ANGELES >> A California woman suspected of fatally stabbing her 18-month-old granddaughter and wounding her daughter and another young granddaughter spent nearly a decade in a state psychiatric hospital and outpatient treatment program before a jury ruled in 2015 that her sanity had been restored.

Nicole Darrington-Clark, 43, was sent to the psychiatric facility after being found not guilty by reason of insanity in the stabbing of her 14-year-old son and throwing of her 10-year-old daughter out of a moving minivan in 2005.

The daughter was the same one who was stabbed Monday, according to police.

Darrington-Clark was transferred to an outpatient facility several years later, and two years ago a Los Angeles County Superior Court jury found that her sanity had been restored, which meant she no longer required court-mandated psychiatric treatment.

Dr. Elyn Saks, a law professor at the University of Southern California with expertise in mental health law, said in insanity cases the accused are given the opportunity to resolve their mental health issues through treatment. That can happen quickly, over a long period or never.

Saks said the person can petition the court for a trial — either before a judge or jury — to prove their sanity has been restored, they understand right and wrong, and no longer are a danger to themselves or others.

Ricardo Santiago, a spokesman for the Los Angeles County district attorney’s office, said his office “strongly opposed” Darrington-Clark’s petition. He noted that unlike criminal trials, jury verdicts in restoration of sanity cases do not have to be unanimous.

An attorney who represented Darrington-Clark at her hearing and a doctor who testified on her behalf did not immediately respond today to requests for comment. A spokesman at the California Department of State Hospitals said officials can’t comment on individual cases.

Darrington-Clark’s sister, LaShunda Clark, and father, Samuel Clark, said today they were concerned about her well-being once treatment ended but added that she seemed to improve.

Late last year her condition took a turn for the worse and she left her husband and 5-year-old son, who has special needs. The father and sister said they were not involved in the restoration of sanity hearing.

Darrington-Clark eventually returned to the family’s Riverside home and on Monday, she went to visit her daughter and granddaughters, her sister said. She said she doesn’t know what prompted her sister’s actions at the apartment in Colton, about 60 miles (97 kilometers) east of Los Angeles.

“None of us has slept in the last two days. It has been terrible for our family,” LaShunda Clark said. “I just don’t understand. We don’t know. We’re just asking God to just keep her safe.”

Investigators have not said if they determined a motive for the attack that killed 18-month-old Damani Trouter. The two wounded victims, whose names were not released, were hospitalized in stable condition.

Darrington-Clark was arrested today in San Bernardino after deputies found her in a car parked behind a business.