SAN JOSE, Costa Rica (CBSNewYork) — National Transportation Safety Board investigators are headed to Costa Rica to assist local officials as they investigate a plane crash that killed a family of five from Scarsdale.

Bruce and Irene Steinberg and their three sons, 19-year-old Zachary, 18-year-old William and 13-year-old Matthew, were among the 12 people who died when the plane crashed Sunday.

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“I’m living a nightmare, my girls are living a nightmare,” Bruce’s sister, Tamara Steinberg Jacobson, said. “I hasn’t really connected yet that, you know, I lost so much of my family.”

Jacobson found out the news while on vacation with family in Florida. Just a few days before, she was with them in Miami, celebrating her older brother Bruce’s 50th birthday.

“We had wonderful days and nights together. We were together as a whole family and on Monday, he was flying out to meet a tour, going to Costa Rica with a bike company and that’s the last time I saw him,” she said.

“Obviously, I didn’t really believe it at that time,” she added. 

Longtime nanny Olga Villatoro also said goodbye to the family at their Scarsdale home before their trip.

“I say bye, bye good luck, hugs, I love you, I’ll see you next year,” she said.

But they never made it back. The small plane went down soon after taking off from the Punta Islita Airport, killing them.

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“We were told that the crash happened right upon basically entry into the air,” Jacobson said.

“I don’t understand. Now, I don’t understand, is this true?” said Villatoro.

The Steinberg family left a mark on their community. The father was successful in finance, the mother a social worker. The oldest, Zachary, was a sophomore at Johns Hopkins University studying chemical and biomolecular engineering.

“Beautiful kids, respect me always, intelligent, smart,” Villatoro said.

The family hopes to bring the five bodies home soon, so they can hold a memorial service.

Also killed in the crash were the two local pilots, operated by the Costa Rican airline Nature Air, and another family of four from Florida — Mitchell and Leslie Weiss and their teenage son and daughter.

The two families were part of a tour group led by Amanda Geissler, who was the 10th American killed in the crash, CBS News reported.

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Nature Air is said the pilot had more than 20 years of experience flying that model of aircraft and called the incident an “unfortunate tragedy.”