Otty Sanchez's plea was accepted by the court on Thursday.
Scott Wesley Buchholz-Sanchez was just 3 weeks old when he was killed.
His aunt called 911 after she arrived home to find the baby dead and Sanchez wailing that the devil had made her kill the child. Sanchez can be heard on the 911 tape yelling, "I didn't mean to do it! He told me to!" the Associated Press reported.
-- Lance Murray