MASSAPEQUA PARK, N.Y. (CBSNewYork) — A teenager’s courage helped save lives from a ferocious fire on Long Island.

She noticed flames coming from her neighbors’ house and got three people and their dog out of their burning home, CBS2’s Carolyn Gusoff reported Wednesday.

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This house in Massapequa Park used to be home to eight members of an extended family.

On July 24, the Kliperas lost everything but their lives. They credit their lifelong next door neighbor 19-year-old Antonina Barry, who was in her own backyard when she saw fire on their patio.

“At first it really just looking like a small grill fire and it just progressed very fast,” Barry said. “The flames were just growing.

The smoke billowed, but no one was running out. So Barry ran in yelling, “The house is on fire! There’s a fire! We have to go out the back! Let’s go! Come on!” she said.

The grandmother and two oldest sons were unaware. Barry and her boyfriend urged everyone out then carried the dog out as the fire closed in.

Minutes later, an explosion from a propane tank consumed the house. Fire officials have no doubt Barry’s actions saved lives.

“She’s an extraordinary young lady. Not many people have the wherewithal to put themselves in harm’s way in order to save their fellow neighbor,” said South Farmingdale Fire Department Chief George McFarlane.

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“Oh my gosh, she saved our family,” said Carrie Klipera. “Nina’s bravery is beyond anything I can ever, ever comprehend… This is just stuff, this can all be replaced. But our life, and our kids’ life, and my mother’s life and my dog’s life can never, ever be replaced, and Nina’s a hero and she made that happen.”

“I don’t feel like a hero,” Barry said. “I would do it again tomorrow because it’s lives.”

As if that’s not enough, she also launched a GoFundMe page for her neighbors to help them rebuild.

“It just shows you how good humans are,” said Klipera, whose home may be deemed uninhabitable.

Meantime Barry, a sophomore at Farmingdale State College studying to become a dentist, can add “humble lifesaver” to her resume.

“I don’t think they would have made it out of the house without Nina, honestly,” said another family member. “Nina is our guardian angel.”

A family that lost everything said they gained something most important: faith in humanity.

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They believe their smoke detectors didn’t go off because the fire started outside, possible from an electrical issue. The cause is under investigation.

Carolyn Gusoff