The teenager who pleaded guilty to stabbing 14-year-old Stefanie Rengel and leaving her to die in a Toronto snow bank is at a moderate risk of re-offending, a court psychologist said Wednesday. 

Dr. Lisa Ramshaw says the 19-year-old has a 58-per-cent chance of committing another violent crime within the next 10 years.

The teen can only be identified as D.B. because he was four days shy of his 18th birthday at the time of the murder.

He lured Rengel away from her home on New Year's Day last year, and stabbed her six times.

She used her last breaths to utter a name that sounded like D.B.'s.

Ramshaw found that D.B. murdered her because of a "unique form of repetitive bullying," that D.B. was too emotionally immature to handle.

D.B. pleaded guilty in April, saying he killed Rengel because of pressure from his girlfriend Melissa Todorovic, who was jealous of the girl even though the two had never met.

Todorovic sent D.B. hundreds of Facebook, text and instant messages for months, demanding he kill Rengel, threatening to withhold sex until D.B. carried out her orders.

The judge in her case called her a "puppet master." In her trial, psychiatrists found her manipulative and unable to show empathy.

But Dr. Ramshaw found that D.B. is able to express remorse.

The psychiatrist's testimony came during D.B's sentencing hearing.

In the same courtroom, Rengel's mother said she agonizes over not knowing what happened to her daughter in her final moments of life.

"I lie awake at night wondering if he spoke to her before he plunged in the knife, over and over," Rengel's mother Patricia Hung said in her victim impact statement.

"Did Stefanie beg him to stop, scream in pain, call my name? Did he just laugh at her and run? Did she know she was going to die?" she said.

Rengel's brother Ian says he wishes he could talk to his sister every day.

"There are things that I need her for. I'm older now, almost 14, just like her and I feel like she only knew me as a little kid. I wish she could see me grown up so that we could hang out more."

Prosecutors want D.B., whose hearing will likely end Friday, sentenced as an adult.

Todorovic, 17, was sentenced to life in prison in July. Her name can now be reveled because she was sentenced as an adult. She will have no chance of parole for seven years. Her family has said they will appeal the murder conviction and the adult sentence.

She is currently serving her sentence in a youth facility but will be transferred to adult prison when she is 20 years old.

With a report from CTV Toronto's John Musselman