WATCH: Jarring New Video Shows The Moment A Semi-Truck Plowed Into Van, Killing 7

"CBS This Morning" has obtained jarring new video of the moment a semi-truck plowed into a church van killing seven people in January near Gainesville, Florida. Five of the victims were on their way to Disney World.

The footage is a key piece of the National Transportation Safety Board's investigation, which is now in the midst of determining the probable cause of the crash. The agency had not been able to immediately to deploy to the scene because of the government shutdown.

As federal investigators try to determine the cause, we're hearing for the first time from someone who was inside the van.

 "I remember closing my eyes and thinking this is it. We're gonna die," Ali Laborde told CBS News' Kris Van Cleave.

Laborde – 31 weeks pregnant – was a chaperone in the church van headed for Disney World January 3. She woke up on the pavement bloodied, surrounded by debris, the burning 18-wheeler and bodies.

"I kept telling myself, 'everyone's okay. They're just hurt.' I didn't realize the severity. I didn't realize that there were five children that there weren't alive," Laborde said. 
 
Her 13-year-old daughter Cara and Cara's cousin Cierra were among those five young lives lost on Interstate 75 that day. Ages 9 to 14, all were from the same small Louisiana town of Marksville. They'd saved up for the Disney World trip for a year. Laborde learned of her daughter's death from her hospital bed.

"I said, 'No, I don't want you tell me. I don't want to hear that. I don't want you to tell me that my daughter's gone. I don't want you to tell that she's not here anymore," Laborde said.

Her other daughter, Chelsey, survived but she'll wear the scars from the accident forever. Laborde and other survivors are now suing, alleging negligence and wrongful death. Lawyer Kurt Arnold, who represents most of the victims, believes the accident was entirely preventable.  

"That Eagle Express truck came at that van like a missile," Arnold said. "If you've looked at this dashcam, this should've never happened."

One of Laborde's cherished memories is a video of the day she told Cara, Chelsey and her son Carson that they were going to have a little sister. Cara, who hoped to be a math teacher one day, used her Christmas money to buy presents for the sister she never got to know. The packages were waiting for Laborde when she got home from the hospital.

"I feel such a weight, such a heaviness. I feel like I'm livin' a nightmare, like I'm livin' someone else's life," she said. 
 
But despite all that day's horror, baby Cambrie wasn't hurt. Just weeks later, she was born healthy and happy. Her name means angel. A miracle born of tragedy.

Via email, Eagle Express Lines General Counsel Aaron Gunderson confirmed the company is a contracted postal carrier. He tells CBS News: "Our company meets or exceeds all federal regulations as well as the more strident requirements of the U.S. Postal Service. We take safety very seriously.

We mourn the tragic accident of January 3rd and the loss of lives as well as the injured. The families involved have remained in our thoughts and prayers. We reached out to the families and their lawyers, who were retained within two days of the accident, and offered immediate financial assistance for travel, medical and funeral expenses. In addition, we met with those same lawyers within a week's time and agreed to voluntarily provide all the documentation the lawyers requested.

We lost a life in this tragedy as well. Mr. Holland was an excellent driver and had driven this same route hundreds of times. He is deeply missed by his friends and family. It appears that he suffered a sudden medical emergency that rendered him unconscious, thus leading to the accident. "

Eagle Express Lines CEO Wayne Hoovestol provided CBS News with a statement: "We are deeply saddened by this tragic accident.  We continue to mourn the loss of life, including our former colleague Steve Holland, and the impact it's had on so many lives. Safety is our No. 1 priority; we take it very seriously. We've cooperated fully with both the National Transportation Safety Board and the Florida State Highway Patrol in their investigations. We have rigorous protocol to ensure the safety of our drivers and those who share the roads. Our company consistently meets or exceeds all federal regulations as well as the more strident requirements of the U.S. Postal Service. The families remain in our thoughts and prayers."

Lawyer Kurt Arnold, of Arnold & Itkin, represents the LaBorde family, responded, "Despite clear liability and devastating consequences, the defendants have attempted to insulate themselves and limit their potential financial exposure resulting from this deadly crash. The defendants have provided no proof or evidence to support any claim of medical emergency or justification for their driver's conduct. The defendants' unwillingness to accept full responsibility has necessitated the lawsuits recently filed in Chicago."

The National Transportation Safety Board is still investigating and thus has not commented on any factors that may have caused the crash.

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