Gloria Arroyo faces up to 20 years in prison when she's sentenced for aggravated manslaughter in January. She could have faced life had she been convicted of murder at trial.
Arroyo was 18 in 2008 and visiting a relative in Paterson, N.J., when authorities said she plunged a knife into 6-month-old Jose Bell 10 times.
In court Wednesday, Arroyo first said she stabbed the baby because she had visions of her boyfriend coming at her with an ax.
Under questioning by the prosecutor, the Phoenix, Ariz., resident changed her story and said she was upset because the baby's father didn't want a relationship.
Information from: The Record, http://www.northjersey.com