(CNN) Hope Forti says her husband was many things -- but most importantly, a father.

"He wanted his first identity to be a dad and a foster dad," she said. The couple has a son, Max, and were foster parents to four other children. Two weeks ago, Forti found out she was pregnant. "It was very important to him that we normalize the idea that people need to be involved in foster care or in some way of helping children and families who need it."

Kyle John Forti was one of the four Americans killed in a helicopter crash in Kenya on Sunday. The US Embassy identified two others as Anders Asher Jesiah Burke and Brandon Howe Stapper. The fourth American has been identified as David Mark Baker, a US State Department spokesperson said. The pilot of the helicopter, Mario Magonga, also was killed.

The helicopter crashed in the Central Island National Park in Lake Turkana, on the country's northern border, Kenya's Civil Aviation Authority said.

A local news outlet reported that two helicopters had taken tourists to the island, which borders Ethiopia and is known for its colony of Nile crocodiles. The other helicopter landed safely, Kenyan police said.

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