She died one month later from heart failure in a Brazilian hospital where she had sought treatment on Sept. 26 for an unknown illness she had developed two weeks after giving birth to son, Keith. Her death came less than 48 hours after a doctor failed to notice her white blood cell count was dangerously low and sent her home with prescriptions for medicine to treat stomach bacteria, according to the family.

Now, her family's seeking answers and trying to raise money to help her husband, Ronaldo, left to care for four children under the age of 7, who still don't know their mother is dead. The hospital where she died has reportedly denied any failure of care. The cause of her swift decline is still unknown.

Amber's distraught husband has hired attorneys to expedite an autopsy based on tissue samples taken before Amber died. And on Thursday, he placed his wife's body on a plane back to the Bay Area. His children will follow as early as Monday.

"If it wasn't for my children, I wish I had died," said Ronaldo, a native of Brazil who met Amber when the two worked at North Beach Pizza in downtown San Mateo. "The pain is so much. It's so horrible."

The couple arrived in Goiânia, a city in the central Brazilian state of Goiás, in April to attend Ronaldo's sister Jacqueline's wedding in July. Against her mother's wishes, Amber decided to stay a few months in Brazil with Ronaldo's family and give birth there.

"I want you to pinch me to wake me up and make it go away," said Amber's mother, Joyce Hart, who worked at the San Mateo County Times from 1981 to 1996. "It's an absolute nightmare. I was afraid she would die down there and she did."

Everything was fine until two weeks after Keith's birth, when Amber got an infection in her breast. She was treated, but other symptoms developed: headaches; stomach, throat and back pain; and a fever that reached 106 degrees.

On Sept. 26 Amber returned to the hospital, where the doctor who had delivered Keith ordered a battery of blood tests, one of which showed Amber's white blood cell count had dropped to 476, Ronaldo said. A normal range is upward of 4,000. But the doctor missed this crucial piece of information, he said, and diagnosed her with a routine stomach infection. She prescribed four medications, including one that can lower white blood cell levels.

Amber fell ill again the next day and had to go to a second hospital, where another doctor missed the white blood cell results, Ronaldo said. By the time a third doctor registered the problem Friday morning, her count had dropped to 100. It was the first Ronaldo had heard of it -- his wife was dead within hours.

Ronaldo said the third doctor told him Amber's body had been ravaged by infection, possibly stemming from her C-section. Others physicians speculated she had leukemia.

"I really want to know the truth," said Ronaldo, who claims doctors at both hospitals were negligent for missing the threat to Amber's life.

Attempts to reach the hospitals by this newspaper were unsuccessful. The team at the Centro de Atendimento Integral à Saúde, the Goiânia hospital where Camargo died, responded to local media coverage by saying that there was no failure in her treatment.

Ronaldo is coming to grips with the fact that Amber, so full of energy and life, is gone. He is summoning the strength to tell his two oldest children -- Jasmine Leigh, 6, and Michael Brian, 4 -- that their mother won't be coming back from the hospital.

"I don't even know how to start," he said. "It's so heartbreaking."

On top of his grief, Ronaldo has medical, funeral and other mounting bills to pay. He's been out of work since undergoing an operation on his corneas in 2010. Anyone who wants to help the Camargos financially can contact Joyce Hart at joicee@sbcglobal.net.

Amber Hart was born at the old Peninsula Medical Center in Burlingame and graduated from Peninsula High School in San Bruno. She and Ronaldo married in 2005 and moved to Sacramento in 2010.

"She was the greatest woman there is," he said. "If you met her, there was no way you could not like her."

Contact Aaron Kinney at 650-348-4357. Follow him at Twitter.com/kinneytimes.

Staff Writer Karen de Sa contributed to this report.