Survivors of the Sandy Hook massacre are torn between celebrating their high school graduation Wednesday and remembering their 20 classmates who lost their lives in one of the deadliest school shootings in U.S. history.

Lilly Wasilnak, 17, said graduation always seemed so far away “but now it’s here and you’re ready but I think we can’t forget that there’s a whole chunk of our class missing.”

Wasilnak joins Newtown High School seniors walking across the stage as they embark on the next chapters of their lives. She told The Associated Press the accomplishment brings “very mixed emotions.”

“Trying to be excited for ourselves and this accomplishment that we worked so hard for, but also those who aren’t able to share it with us, who should have been able to,” she said ahead of the ceremony.

The 20 first-grade students and six educators killed in the Dec. 14, 2012 shooting at Sandy Hook Elementary School will be honored during the graduation but details have not been made public, the AP reported.

Wasilnak said she is still trying to decide what she plans on studying in college but will continue to speak out against gun violence.

“I wanted to turn such a terrible thing into something more, and that these children and educators didn’t die for nothing,” she said. “Of course, it was awful what happened to them, and it should have never happened, but I think that for me, something bigger needed to come out of it, or else it would have been all for nothing.”

Grace Fischer, 18, was in a classroom down the hall from the shootings. Fischer, who hopes to become a civil rights lawyer, said the killings were a “core memory growing up” for her and others.

“I think that took away a lot of the joy that we could have experienced when we were six years old,” she said. “And I can’t really remember many times before the shooting so in that sense, it really did take over those really innocent times and it really forced us to grow up so fast when we didn’t need to.”

Emma Ehrens was one of 11 children in a classroom to survive the shooting. She and others fled as the gunman stopped to reload.

“I had to watch all my friends and teachers get killed and I had to run for my life at six years old,” she said. “Just growing up with having the fear and the what ifs of what could have happened if I stayed.”

“Because I was going to be next.”

Ehrens, 17, said she is “mournful” but likes to think “that they’ll be there with us and walking across that stage with us.

After graduation, she plans to study political science and the law and wants to become a civil rights lawyer or politician.

Ella Seaver, 18, said the “what ifs” have “spoiled a lot of precious moments” for her “because you always remember that they are not there.”

Seaver plans to study psychology in college and hopes to become a therapist as a way to give back.