TORONTO - A sentencing hearing for a 17-year-old girl convicted of first-degree murder in the stabbing death of another Toronto teen has been rescheduled for next week.

Stefanie Rengel, 14, was stabbed on New Year's Day 2008 and left to die on a sidewalk near her east-end home.

The Crown successfully argued that the convicted girl, driven by jealousy, used sexual blackmail against her boyfriend to push him into murder.

The boyfriend pleaded guilty to killing Rengel and will be evaluated by a forensic psychiatrist before his sentencing hearing, scheduled for June 25.

The sentencing hearing for the girl, who was found guilty by a jury, will now begin May 20 after being scheduled to start today.

The Crown prosecutor is seeking an adult sentence for both the boyfriend and the girl.

Rengel, a Grade 9 student and the daughter of two Toronto police officers, was stabbed six times.