"I said, 'I'm proud of you. I love you. Have a good day,' and that was the last thing I said to him," said Kelly Welling, the mother of Wesley Welling.
The mother found out about her son's death from her daughter, who was just a short distance away from the crash. The crash happened on the mother's birthday.
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"I get the call from my daughter Hannah. There was an accident and he was unconscious and they were doing CPR and they did CPR the whole way to the hospital," Kelly Welling said. "That is where he passed. By some miracle, my daughter wasn't standing right next to him because it could have been both of them."
Wesley's sister Hannah said she heard a skidding car and everything happened fast.
"I'm just concerned about his sister because she witnessed the accident," said Kelly. "I just can't believe it's real. I'm expecting him to walk down the stairs and still hear his voice."
Three of Wesley's fellow classmates were injured in the collision and investigators believe the driver may have intentionally struck the victims.
A makeshift memorial, comprised of flowers and candles, was created in honor of Wesley at the crash site. Students stopped and paid their respects on their way to class Wednesday morning. Nearby, a bus stop shelter was undergoing repairs after being damaged in the violent crash.
Olivia Ludwig's friend, who remained hospitalized, was among the three surviving victims.
"Her femur is broken and she had surgery last night to repair it," Ludwig told ABC7. "She's up now, and she's OK, but there's a chance that she's going to be in a wheelchair for eight weeks.
"She has so much, so much going for her, and I'm just really upset to have to see that all go down the drain because of this."
The suspect in the crash was identified as Austin Eis. Authorities said the 24-year-old began a crime spree 13 miles from where the crash occurred. Eis, a former Westlake High student, allegedly stabbed an employee at a Walmart store in Simi Valley. Eis then made his way to his parents' home in Camarillo, where an argument led to police being summoned.
That incident was followed by the collision in Thousand Oaks.
Eis remained in custody Wednesday, according to the Ventura County Sheriff's Office. He is expected to be arraigned on multiple charges Thursday. His bail has been set at $5 million.
"I felt like I've been able to be kept in this bubble for so long," Ludwig said. "And just seeing how easily one person's bad intentions can injure and hurt so many families, and so many people, really breaks my heart."
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Thousand Oaks Police Chief Jeremy Paris said he and his department's officers "know the people here in the community, we all have connections, and it's very difficult.
"The officers that are on scene, you know, it's very, very difficult for them."
A vigil was held Wednesday evening at Calvary Community Church in Westlake Village, where dozens of people came together to mourn, including teachers, parents and lots of students, who said the death of Wesley has been difficult to process.
"Work today was all optional," said Malia Smith and Natalie Weston, two students. "Most people left school early and there were a lot of counselors around trying to help us out with grief. But the one thing is our community is all here together and you can feel the love and the support around our school."
As of Wednesday morning, the online fundraiser in honor of Welling had garnered more than $118,000 in less than 24 hours.