The Sierra Club began air quality tests in 2006 after receiving health complaints. The environmental organization found that about 83 percent of trailers tested had formaldehyde levels up to three times higher than the EPA workplace limit.
The Huckabees' symptoms started just days after moving into their first trailer in Kiln, Miss. Lindsay, 26 and pregnant, began having migraine headaches, and the four children had constant upper respiratory problems.
One daughter, who had been asthma-free for two years, had a recurrence, and Lindsay had pre-term labor contractions during her latest pregnancy and delivered five weeks early. The baby, now 2 years old, has been in the hospital with asthmatic bronchitis.
Their doctor finally advised testing the first mobile home and found double the acceptable levels of formaldehyde. FEMA replaced that home with another, which also tested positive for formaldehyde.
Formaldehyde, a toxic chemical most often used for embalming, is used as a glue in building materials. Under hot, humid conditions it can leak into the air.
For that reason, FEMA said it wants all trailer occupants out by the summer, when temperatures rise and hurricane season begins again.
"This is a real vindication for people that have been trying to raise the alarm about this for two years," said Becky Gillette, a volunteer for the Mississippi Sierra Club, who led the effort to test trailers.
But the Huckabees and others don't want to move, and say government efforts are not enough. Steve Huckabee earns $38,000 a year as a land surveyor, and Lindsay has just taken a job at a Waffle House restaurant to help with the bills.
"All the medicine they have to buy is what a mortgage payment would be, and she's not getting any help," said Gillette, who has heard the health woes of hundreds of families whose children are sick. "They can't save money because they are sick all the time and the kids are out of school. How can they rebuild?"
Those who have been working with victims say there is already a shortage of affordable housing in the Gulf region. Huckabee said rents in her town have jumped from about $900 a month to up to $1,500 a month.
"They claim they are going to get everyone out really quickly," said Huckabee, who testified to Congress on the family's health problems. "But they did that did this before, and I don't think there were enough hotel rooms. I guess we are going to have to wait and see."
The CDC said they would go "door to door" to hand deliver individual home tests to begin a registry of health problems and the long-term effects of the formaldehyde exposure. A broader-based children's health study is also in the works.
At the press conference, FEMA head R. David Paulsin vowed "to continue aggressive action to provide for the safety and well-being" of trailer residents.
Case workers will offer people advice on their medical, employment and educational needs, he said. They will also assist with the relocation and care of pets and help provide furnishing.
"We do care about these people, but we did not have a lot of information," said Paulsin. "[The trailers] were the only toolbox we had at the time."
Sierra volunteers say FEMA has "side-stepped" the larger issue of who is going to pay for the long-term health effects of the formaldehyde exposure.
"They ought to be embarrassed," said Sierra's March, who tested 30 trailers herself. "I never heard such a long list of promises from an agency that's not shown us they are worthy of our faith. I am praying they are not giving us false hope."