Mary Lee Collins, right, pleaded guilty Monday to first-degree murder in the death of her 22-month-old son, Joshua. Investigators said he was kicked in the head and hurled down stairs when he would not stop crying. The case helped reform the way the state runs its child protection system. Under a plea agreement, Collins received a life sentence with no chance of parole for 25 years. She also was sentenced to 15 years on aggravated child abuse. The sentences are to run concurrently.