Fourteen-year-old Ariane Villanueva said she feels the weight of the world on her shoulders.
"You wouldn't think it would happen. You wouldn't think it would happen in your city but it actually could," she said.
Her friend Gracie Anne Muehlberger, 15, died at the hospital after a 16-year-old classmate stood motionless in the quad at the Santa Clarita school, reached into his backpack, then opened fire, wounding five others before shooting himself in the head. It was just after 7:30 in the morning, when many students were arriving for the day.
Fourteen-year-old Dominic Blackwell succumbed to his injuries at the hospital.
The other teen students injured have not yet been identified, but one was released from the hospital and two others were expected to be released soon.
Ariane says since the shooting, she's been feeling survivor's guilt.
Friends sent text messages from inside Saugus High School warning her.
"Saying like there were gunshots and don't go to school, don't go to school," Ariane said.
She turned on the news to see what was going on, and was devastated.
"When it was released that Gracie died, I didn't believe it and I didn't want to believe it," she said.
Ariane met Gracie at Arroyo Seco junior high, one of the schools near Saugus High School that was also put on lockdown when the shooting erupted Thursday.
The two girls bonded in 7th grade choir.
Ariane created a video tribute to express what's impossible to say in words and posted it to Instagram.
In the video, music plays as videos of Gracie transition, her wide smile — complete with braces — lights up the screen as Ariane and she laugh, dance, and shuffle through Snapchat filters. In one image, Gracie is wearing a homemade costume as Damian from the cult favorite "Mean Girls," with a sign on her chest that reads, "She doesn't even go here!"
"She was really charismatic. She cared a lot about her friends, she cared a lot about them," Ariane said through tears.
The thought of going back to school Monday without her friend is surreal. She remembers a carefree time, when the two laughed after Gracie was willing to go the extra mile to find her friend's lost phone.
"She ran through crowds of people just to find my phone, and it was in my pocket," Ariane said.
She encouraged everyone to be more like Gracie.
"We just have to love each other more. That's all just spread the kindness you know," she said.
Ariane said she'll miss Gracie's laughter the most and will pray for all the victims' families.
Gracie's family members had taken to social media to express their grief.
"My heart is killing me right now, you are the best sister I could’ve asked for, I just know you’re my guardian angel now. I love you Gracie," her brother said via Twitter.
The two students, 14 and 15, still hospitalized were in good spirits Friday.
"Once we were done, they were both sitting up, smiling and talking," said Dr. Boris H. Borazjani, of Providence Holy Cross Hospital. "They held their composure, despite being shot. And, being shot in the torso is a big deal."
The 15-year-old girl was shot below the belly button, while the other was shot in the lower right abdomen, doctors said.
The entirety of the shooting last 16 seconds, captured on surveillance cameras.
It wasn't immediately why the shooter brought the weapon to school and began firing.
Authorities were working to trace the origins of the .45 caliber handgun.