Omaha, Neb. ? When a Brazilian missionary family who came to work in the United States first vanished, family members thought they had gone on a spiritual retreat. But as months passed and no one heard from Vanderlei and Jacqueline Szczepanik and their 7-year-old son, they began to fear the worst.

Now, their fears have been realized. Nearly two years after the family disappeared from the school they were renovating into a church center in Omaha, the remains of their son, Christopher, were found at the bottom of the Missouri River, and authorities say they have more evidence he and his parents were killed in a dispute over money.

The discovery of Christopher’s body last week has prompted a new push to bring one of the three suspects back to the U.S. to face charges and fresh grief for family members and friends who have waited years to find out what happened to their loved ones.

“We always had high hopes they would be found alive, but then the three men were arrested and we lost hope,” Christopher’s 20-year-old brother, Darcy Klein, told The Associated Press in Brazil.

“All I ask at this point in the name of the three who I will no longer see alive and who were tortured and killed, is that justice be done.”

At the time of their disappearance in December 2009, the Szczepaniks had been living in Omaha for five years after moving from Florida to renovate an old school into a center for the Assembly of God church, said Joao de Brito, the site manager of the school where children participated in art and other social events.

De Birto, who also is Brazilian, described Christopher as a respectful child with a huge smile who struggled to carry his book-filled backpack and violin case.

“There was something about him, I don’t know how to describe,” de Brito said. “He was not like a regular kid.”

After the family disappeared, anxious relatives and friends spent months trying to figure out what happened. Klein’s sister traveled to Omaha to help with the investigation. Aside from finding their abandoned Nissan pickup truck and 1995 Dodge Caravan, search after search turned up empty.

The family had vanished, and no one could explain why.

In May 2010, three men, who were from Brazil and had worked for the family, were first charged with running up thousands of dollars in charges on the family’s credit cards. A break in the case came eight months later, when one of the men, Valdeir Goncalves-Santos, was charged with murder. He later made a deal with prosecutors in exchange for being sentenced to 20 years in prison.

Another of the men, Jose Oliveira-Coutinho, was ordered last week to stand trial on murder charges. His attorney declined to comment Wednesday. A warrant has been issued for the third man charged, Elias Lourenço-Batista, who is living in Brazil.