Transcript for Las Vegas shooting survivors reunited with hero cop

A family that lived through the nightmare in Las Vegas is crediting an off-duty police officer with saving their lives. Yeah, he stepped in to help them during the chaos that unfolded that night and ABC's Abbie Boudreau was there for it. The emotional reunion. Come here, boys. Oh, so happy to see you guys. Reporter: This emotional reunion after a heart-wrenching week for Las Vegas after it became the scene of a deadly mass shooting. Jenny, Adam and their three young sons at the route 91 harvest festival, normally an annual family tradition. We look forward to it every year, the day the tickets go on sale we buy tickets, we book our rooms. Reporter: Quickly turning to terror. We came from a real high and then just suddenly fell. Panic. Yeah. It happened that fast. I had him on my shoulders. For the first 30 shots. Yeah. And we dove on the ground and that's when Lance came and helped us. Reporter: The man they now call their hero happened to be an off-duty Los Angeles county deputy. Lance moorman. I'm not hero. I just did what needed to be done. He started yelling get the kids down. Had his hands over us, his head down and telling people don't move. Don't move. You guys stay here. I'm going to keep you guys safe. He kept telling us over and over again I'm not going to let you guys die. I'm not going to -- Yeah. Yeah. Yep. Reporter: Finally it was time for the family to run. That's when they were separated from Lance. Now finally reuniting. Come here, boys. Oh. So happy to see you. Thank you. It was such a terrible time. Absolutely. But you guys did so well. We couldn't have done it without you. No. Adam. Reporter: For "Good morning America," Abbie Boudreau, ABC news, Los Angeles. Complete strangers just embracing and that's one of the stories. I mean despite all the tragedy and massacre you have complete strangers helping one another and so many tales of heroism. Heroism, true hero. All right, thanks to Abbie Boudreau for that story and

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