NEWPORT, Ore.  — The Oregon mother who killed her 6-year-old son by tossing him off a bridge on the Oregon coast has been sentenced to life in prison and will be eligible for parole after 25 years.

Jillian McCabe appeared before a judge late Monday afternoon and entered into a plea agreement with the state and was convicted of one count of murder. According to court records, McCabe had earlier pleaded not guilty to charges of aggravated murder, murder, first-degree and second-degree manslaughter in the death of her son, London. As part of the plea agreement, the remainder of the charges she had faced were dismissed.

London McCabe’s father speaks at a press conference, Feb. 23, 2016 (KOIN)“I will miss my son forever,” said London McCabe’s father Matt at a press conference, Feb. 23, 2016 (KOIN)

A judge previously delayed McCabe’s arraignment pending a mental health evaluation.

Police said McCabe called 911 on November 3, 2014 and reported throwing her son from the Yaquina Bay bridge in Newport. Searchers found his body hours later.

At a press conference Tuesday, Lincoln County District Attorney Michelle Branam revealed more stunning details about the case. Branam said it was obvious that McCabe spent weeks planning her son’s death.

Cell phone and Internet records show McCabe researched drowning methods. She also researched other cases of mothers who had killed their children. Branam said McCabe had already planned her defense, hoping to be found guilty but insane.

“This was a premeditated murder of a 6-year-old. He was completely trusting. He was defenseless against her. She took him to a location where there was no chance of survival.”

Despite relatives and friends saying McCabe struggled with mental illness and had trouble caring for her son and her husband, Matt, who was diagnosed with multiple sclerosis, Branam claims this case isn’t about a broken mother at all. Branam said McCabe simply wanted a better life, free from her son and husband.