By Cleve Bryan

PHILADELPHIA (CBS) — Dozens of teens packed an Atlantic County courtroom Tuesday for the trial of a man accused of killing one of their friends.

Nicholas Garreffi from vineland faces charges of vehicular homicide and assault by auto for crashing into a car full of mainland high school students in august of 2014.

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Three girls were hurt and 14-year-old Aisling Cooke died.

“I have missed her dearly and it’s a day by day process still,” Molly O’shea, Cooke’s friend, said.

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“I’ll go through my classes and my day and I’ll wonder what would it be like if she was here with us,” Jules Cino, another one of Cooke’s friend, said.

About to become a starter even as a freshman, Mainland retired Cooke’s No. 4 soccer jersey.

She would’ve been a senior next month.

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Authorities say Garreffi was driving under the influence of alprazolam, commonly known as Xanax. They say he crossed the yellow line, hit a box truck, then slammed into the car full of girls, who were driving to a charity soccer tournament.

A toxicology expert testified that even low-levels of the drug can impair a person’s driving.

Ayako Chan-Hosokawa, a forensic toxicologist, said, “The effect is to relax your body system, and therefore you tend to have poor coordination, difficulty following instruction…you have significant drowsiness”

Garreffi’s attorney pointed out effects can vary significantly from person to person.

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Geralyn Williscroft, a parent of an injured child involved in the fatal crash, said, “The defendant made a terrible choice that day and we suffered the consequences of that choice, and these girls are living with that every single day.”

Both of Geralyn Williscroft’s daughters were in the car with Cooke. She says it’s something they struggle with everyday.

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“They have not overcome this; I don’t know if they ever will,” she said.