Phoenix police have arrested a 36-year-old mother of nine on suspicion of first-degree murder in the suffocation death of her newborn daughter.
"Anyone who has a child, particularly a new baby, it tears at their heart," said Phoenix police Sgt. Tommy Thompson. "It shocks them to think a mother, for whatever reason, would ever suffocate or, for that matter, do any type of injury to their newborn child."
Police said Bradley Koistinen found his daughter's body in bed next to her mother around 6:45 a.m. April 8 and called 911.
The six-day-old baby, named Maya, was taken to Paradise Valley Hospital where she died 45 minutes later.
"At this point, nothing seemed out of the ordinary," Thompson said. "The information the officers received initially was that the mother had taken some medication and had fallen asleep."
According to the police report, an autopsy found signs of possible suffocation.
But a review of past Child Protective Services records indicated Maya's death might not have been an accident.
In the report, it's noted Nina Koistinen had made statements about wanting to smother some of her children and that, following what appeared to be an intentional car accident, she wanted her children to go to Heaven.
On Thursday, detectives brought Nina Koistinen in for a second interview.
During questioning, they said she told them what she'd done to her daughter.
"The mother of the baby, she admitted she had purposely suffocated this six-day-old baby," said Thompson.
Police said Nina Koistinen told them she smothered Maya because she thought she had too many children and that she was jealous of the attention her husband was giving the newborn.
Bradley Koistinen attended his wife's initial appearance Friday and made an emotional plea to the court.
"Nina suffers from bipolar, schizophrenia and depression," he said. "And we have tried for years and years to manage it. She has been the greatest mother. We've been married 15 years. To our kids, never once has she hurt any of our kids. I see her deteriorating the last two days - her mental state. I don't know if her medication is right."
Nina Koistinen is being held at the 4th Avenue Jail in downtown Phoenix.
Bail is set at $1,000,000.
Bradley Koistinen tells CBS5 News family members are helping him care for his eight remaining children.
Police said CPS is overseeing the arrangement.
Calls to CPS, regarding past encounters with the family, have not been returned.
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