Ethan Hoac is another face of Victoria's youth knife crime crisis.

For the past two-and-half-years, his family has struggled to comprehend why the 14-year-old's life ended in such brutal fashion.

"I don't know how long this will hurt," his mother Annie Huynh said in a letter to Victoria's Supreme Court.

"I think it will be forever."

On Thursday, Ms Huynh and Ethan's brothers Nicholas, Hao and Nathan stood outside the court clutching a cherished photo.

Minutes earlier, they had watched as Ethan's killer, now aged 19, was sentenced over his death.

In jailing the teenager for a maximum of 17 years, Justice Jane Dixon described the murder as "appalling" and "vicious".

Teenager killed by strangers in unprovoked attack

The court heard Ethan and two friends were set upon while walking nea

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