For more than five years, David Goldman fought to get his son back from Brazil.

Now that they are together again in the United States, Goldman has a parenting struggle ahead: How does a father get to know his 9-year-old son again, especially a boy whose mother has died and who has been transplanted to a country he hasn't seen since he was a preschooler?

"I kind of feel terrible for him," Dr. Alan Hilfer said of Goldman's son, Sean. Hilfer, director of psychology at Maimonides Medical Center in New York, has been following media reports about the case.

"He's going to have a pretty hard time, even though I'm sure his dad will do the best he can."

Goldman, of Tinton Falls, in Monmouth County, N.J., and his son were reunited Thursday in Rio de Janeiro and almost immediately left to return to the United States by chartered jet. They later arrived in Orlando, Fla. Rep. Christopher H. Smith (R., N.J.), who traveled to Brazil several times with Goldman, would say only that father and son wanted to "cocoon" somewhere other than New Jersey for a while.

The saga began in 2004, when Goldman's wife, Bruna Bianchi, took Sean, then 4, to her native Brazil. Bianchi was due back in two weeks, Goldman said, but she never returned. She left Goldman, divorced him in Brazil, remarried, and died in 2008 while giving birth to a daughter.

Goldman, who operates charter fishing boats, had argued for years that Sean belonged to him under an international treaty that sets procedures for dealing with child abductions.

After Bianchi died, Goldman's case started getting media attention in both countries - and then momentum in Brazil's court system. His son's stepfather, part of a family of well-connected lawyers in Rio de Janeiro, continued to oppose the boy's return until Wednesday. One of the stepfather's main arguments was that Sean had grown roots in Brazil and would be better off there.

Judges ultimately found that the case was about abduction, not custody, and returned the boy to Goldman.

People involved in the case say Sean has a tough adjustment ahead.

Other parents who have been reunited with children after long lapses said the change can be heartwrenching, even when there was regular contact, something Goldman has not had. Goldman, who dreams of taking his son fishing, was denied access to the boy until February and had seen him for no more than several hours at a time on a handful of occasions since, and never alone.

Jeanette Vega of New York City was separated from her son, Remi, from 2000 to 2003. After allegations that she abused him when he was 2, he lived with relatives, then in foster care. Vega saw her son regularly while they were apart and he remained in the same city.

But the transition was still difficult when he came back to her, she said. He was accustomed to the rules of his foster home. And he was skittish. "He was always having fears that someone would come and get him," she said.

Vega said it took months just to get him to think of her home as his home.

Smith said Goldman and his son bonded easily when they were together, even though, the lawmaker said, Sean's family in Brazil disparaged Goldman and took steps to make the transition more stressful - including having Sean walk through a crush of photographers on his way to their reunion, rather than slipping him in through a secure garage.

Hilfer said Goldman should spend time first alone with Sean, then gradually introduce him to his new American routine, waiting a few months to send him to school.

"He's a kid who's had many losses," Hilfer said. "There was the loss of his father, the loss of his mother. Now there's the loss of his extended family in Brazil."

Hilfer said it was unlikely Sean would remember much of the people or places he knew as a younger boy in New Jersey. A child that age should adapt, Hilfer said, but the first year or two will be lonely.

Hilfer said the transition would be eased if Sean maintained contact with his maternal grandparents from Brazil. Goldman says he would allow such contact, but his lawyer, Patricia Apy, said guidelines still had to be worked out.

Apy said the real problem was that the child-abduction treaty was not enforced for 51/2 years, long enough to make a return to Goldman harder on the boy.

"There's nothing in the treaties to deal with this issue," Apy said, "because the treaties aren't supposed to take that long."