Story highlights Emily Castro was 19 when she took her baby into a garage and cut her throat, court records say

She admitted to cutting her own neck and wrists and trying to drown herself

Her brother told a court that family had dealt with her mental illness for years

Judge decided she was still aware of right and wrong

A daughter of Ariel Castro , the primary suspect in the abduction of three women found alive this week, is serving a 25-year sentence in an Indiana prison for the attempted murder of her baby six years ago.

Emily Castro was sentenced to 30 years with five years suspended. A judge found Castro guilty but mentally ill of cutting her 11-month-old daughter four times on the neck in April 2007.

An appeal, filed in late 2008, was denied by an Indiana court.

Legal documents state that on April 4, 2007, Castro, 19 at the time, was upset that her boyfriend -- the baby's father -- had moved out of the family's home in Fort Wayne. She took the baby into a garage and cut her neck four times with a knife.

Castro also cut her own neck and wrists.

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Police were summoned to the house by a passerby who came upon Castro's mother carrying the baby and running from the home. Officers found Castro covered in mud, water and blood. Castro told paramedics she had tried to drown herself in a creek, according to an appeals court decision document.

The baby survived.

According to the Fort Wayne Journal Gazette, the defense argued at trial that Castro had suffered from mental depression and became paranoid, thinking her family was trying to kill her and the baby.

The judge found that Castro still had the ability to know right from wrong.

She and her brother Anthony spoke at her sentencing hearing, the Journal Gazette reported

"I don't know how this happened," said Castro. "I want you to know I am a very good mom."

Anthony Castro said his sister was not an animal. The family had dealt with his sister's illness every day, he added.