MONTGOMERY COUNTY, Texas -

A Houston woman charged with killing a Montgomery County mother and kidnapping her newborn son has pleaded guilty to the crime in a plea deal that ensures she will spend the rest of her live in prison.

Verna McClain, 32, entered the plea Tuesday at a court hearing in Conroe and accepted a sentence of life without parole.

McClain is charged with killing Kala Schuchardt outside of a Montgomery County pediatric clinic in April 2012.

Schuchardt's mother, Linda Golden, was in the courtroom to see the sentence handed down Tuesday.

"I was glad she did it ‘cause I know she’s going to prison and she'll never get out. And that she did admit killing my daughter and I'll never be over the pain of losing my daughter," Golden said.

Schuchardt had taken her newborn baby boy for a checkup and was shot multiple times in the clinic's parking lot.

Detectives said McClain admitted to carrying out the attack and abducting 3-day-old Keegan Schuchardt, who was found unharmed hours later with McClain's sister.

"Her motive was as plain as the nose on your face. Her motive was she had a boyfriend, told her boyfriend she was pregnant. She wasn't pregnant. And so she killed Kala. She stalked Kala. She sat in the parking lot picking out the victim she wanted," Montgomery County Attorney Brett Ligon said outside the courtroom after the sentencing.

Ligon initially said he would ask for the death penalty, but after several delays in setting the case for trial, Schuchardt's family agreed to the plea deal. Her mother said the sentence was just.

Besides her infant son, Schuchardt was the mother of two small boys, ages three and six.

"The 6-year-old cries out he loves his Momma, he misses his Momma. The 3-year-old sees her picture and says, 'That’s my Momma. When is she coming home?’ And the baby will never know his mother because of this horrible deed," Golden said.

During sentencing, McClain spoke in a low voice, saying little in the courtroom. Her defense team considered an insanity defense early on, but attorney George Parnham says under Texas law, McClain is not eligible for it.

"Based on all of the circumstances... this was the better solution than to try this case as a death penalty case," Parnham said.

By accepting the plea agreement, McClain waived her right to appeal. Like Schuchardt, she is the mother of three children. They now live with their grandmother in Oklahoma.