Graduation season can be bittersweet for a lot of seniors, but many of the 2024 graduates of Newtown High School in Connecticut are carrying a heavier burden.

The shooting at Sandy Hook Elementary School shook the nation as one of the deadliest school shootings in U.S. history on Dec. 14, 2012, according to the Associated Press (AP).

During the incident, 20 first-grade students and six educators were killed.

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Of the 330 students graduating from the district’s high school on the evening of June 12, 60 are walking across the stage as survivors.

The AP spoke with a few survivors, including Lilly Wasilnak, 17, who was in a classroom down the hall from where her fellow students were killed.

a child looks out the window of a bus in newtown ct

A child gazes out of a school bus window as the bus passes St. Rose of Lima Catholic Church while mourners gather for a funeral service for shooting victim Jessica Rekos, 6, on Dec. 18, 2012, in Newtown, Connecticut. (John Moore)

"I think we’re all super excited for the day," she said. 

"But I think we can’t forget ... that there is a whole chunk of our class missing."

"And so, going into graduation, we all have very mixed emotions — trying to be excited for ourselves and this accomplishment that we’ve worked so hard for, but also those who aren’t able to share it with us, who should have been able to."

Emma Ehrens, 17, was one of 11 children to survive the attack in Classroom 10. 

emma ehrens speaks at a rally against gun violence

Emma Ehrens, center, a survivor of the 2012 Sandy Hook Elementary School shooting, speaks as she stands with other survivors during a rally against gun violence on Friday, June 7, 2024, in Newtown, Connecticut. (AP Photo/Bryan Woolston)

She managed to flee gunman Adam Lanza as he paused to reload, but five children and both teachers in the room were killed.

Ehrens said her graduation day will be filled with "a lot of mixed emotions," the AP reported.

"I’m super excited to be, like, done with high school and moving on to the next chapter of my life," she said. "But I’m also so ... mournful, I guess, to have to be walking across that stage alone … I like to think that they’ll be there with us and walking across that stage with us."

Psychological impact

Many of the survivors have said they've experienced PTSD, anxiety and depression, spending years in therapy since the incident, according to reports.

Dr. Cameron Caswell, an adolescent psychologist in Washington, D.C., sympathized with not only the survivors but also the victims’ families, she told Fox News Digital.

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"The upcoming graduation ceremony for Sandy Hook survivors will likely be a poignant and emotionally charged experience," she said. 

Newtown Memorial

A Sandy Hook Elementary School shooting memorial is pictured in Newtown, Connecticut, on Dec. 23, 2012, after the tragedy. (iStock)

"In addition to mourning the child they had, they may grieve for the child they were supposed to have," she added, referring to the parents. 

Caswell suggested that the families may grapple with "the weight of unfulfilled potential," such as unreachable milestones, college dreams, future careers and the "simple joys of growing up."

"The celebratory atmosphere of the ceremony is likely to amplify the absence of their child, creating a profound sense of ‘what if,’" she said. 

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"They [the parents] may imagine their child participating, sharing in the excitement and reaching a life stage forever stolen," Caswell told Fox News Digital. "This occasion may also evoke a complex mix of emotions beyond sadness, such as jealousy, anger or guilt."

Sandy Hook shooting survivors

Matt Holden and Grace Fischer, survivors of the 2012 Sandy Hook Elementary School shooting, talk about their high school graduation.  (AP Photo/Bryan Woolston; Enid Alvarez/NY Daily News via Getty Images)

She encouraged parents of the victims to allow themselves to feel and express "whatever emotions come up."

"There's no right or wrong way to grieve and no required end date," she said. "Talk about your child, share stories, hopes and dreams."

She also said, "Lean on other parents who understand your pain. Support one another and share your experiences. This can be a powerful source of strength."

sandy hook parents walk away from the scene of the shooting

People leave a staging area outside Sandy Hook Elementary School in Newtown, Connecticut on the day of the shooting. A gunman opened fire inside the school, killing 27 people, including 20 children. (James Keivom/NY Daily News)

Caswell also advised parents to set necessary boundaries and prioritize their needs during this time. 

"This occasion may evoke a complex mix of emotions beyond sadness, such as jealousy, anger or guilt."

"It is not your responsibility to make other people feel comfortable," she said.

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For the parents of survivors, Caswell suggested starting a conversation with the parents of victims and asking about the children they lost.

children and their parents pay tribute to sandy hook shooting victims

Children and their family members pay tribute to the victims of an elementary school shooting in Newtown, Connecticut, on Dec. 15, 2012. (EMMANUEL DUNAND/AFP)

"Give them your full, undivided attention," she said. "Ask open-ended questions and avoid interrupting."

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"Notice if they seem overwhelmed and offer practical support, such as getting them a tissue or water, without needing to be asked."

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She added, "Acknowledge their emotions and allow them to express their feelings freely. Don't minimize their experiences or compare your own feelings."

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The Associated Press contributed reporting.