A former Westchester County high school student has been sentenced to 17 years in state prison for stabbing a 16-year-old schoolmate to death at a Dunkin' Donuts last year. 

Z'Inah Brown pleaded guilty in May to first-degree manslaughter, a class B violent felony, in May in the death of Valaree Schwab, a former classmate of hers at New Rochelle High School. Prosecutors said Brown and several other teens stalked Schwab on several occasions -- and one time, it turned physical, with the group attacking her on a North Avenue sidewalk on Jan. 10, 2018.

As she was being attacked, Schwab dropped her house keys and one of the teens picked them up, authorities have said. The group went to a Dunkin' Donuts on North Avenue and Schwab, desperate to get her keys back, followed them.

She was stabbed inside the restaurant when she tried. Schwab was pronounced dead later that day. 

In court Wednesday, Schwab's sister, Britney Schwab, read a statement on the devastating impact her sister's death has had on her entire family. 

Speaking directly to Brown, she said, "My sister Valaree was only 16 years old and full of life. She was bold, energetic and spirited. Your violent rampage stole a third sibling away from me long before it was their time. I hope that her sudden, untimely death will never be used in a discussion as fuel for hate."

"I hope that, if anything, it can serve as a reminder for young people to find peaceful ways to resolve conflict and for families to hold their loved ones a little closer," Britney Schwab said. "I know Valaree would want us to bury hate and choose peace instead."

In addition to the prison term, Brown will serve five years' post-release supervision. Two other teenagers, Dominique Slack and Carl Booker, both pleaded guilty to first-degree stalking, a class D violent felony, in connection with the attack on Schwab the day she died. Booker was sentenced in March to "shock probation," and will be incarcerated in Westchester County Jail for six months. Slack received the same sentence a month earlier.