Lisa Turkki told police that she intended to kill her sister's family
when she drove to their Katonah home in July but said she was mentally ill and may have "missed some medications."
Her statements, made within hours after the 7- and 9-year-old girls were found bleeding on their kitchen floor, were in court papers filed Tuesday at Turkki's arraignment in Westchester County Court in White Plains on two counts of second-degree attempted murder, a felony, and related charges.
The girls recovered from their wounds after a hospital stay of more than a week.
According to court papers, Turkki called 911 herself, at 9:20 and 9:23 p.m., saying she had stabbed her nieces and needed help.
When police arrived a minute later, Turkki spoke with them outside, telling them the girls were inside and that she didn't know why she had stabbed them. Turki was then taken to the station, where, police said, she revealed her intent to kill the Kellys.
"The defendant stated that she had driven to her sister's home in New York to kill her family and stabbed her two nieces in the kitchen," according to court papers.
Turkki also told officers that she was "schizoaffective" and might have missed some medications. Her last statement, made at 11:04 p.m., expressed regret.
"I feel sorry for what I did to my sister," court papers quote her as saying.
Schizoaffective disorder is a condition in which a person experiences a combination of schizophrenia symptoms, such as hallucinations or delusions, and mood-disorder symptoms, such as mania or depression, according to the Mayo Clinic's website.