Fort Bragg and federal agencies did a site survey before they start extensive testing next week.
One mother says she's skeptical about the latest investigation, based on how she says her family has been treated so far.
Mackenzie Agee says her son Lachlan Agee was born at 27 weeks, but says the preemie was a healthy little boy until they moved into their home on Fort Bragg and he developed a cough.
"They said no, it's not RSV, it's just a cold or something but it never went away, he still had it five months later when he died," she said.
Agee says during that time she tried repeatedly to get another appointment, but was turned away. Then one morning in May 2008, her husband found their son dead in his crib.
"He went over to check on him and felt that he was cold and looked and saw that he was blue, tried to move him and he just yelled at me to call the MPs and not to come upstairs," she said.
The chronic cough is similar to what other families say their babies had before they died on post. The parents say their older children developed eczema and they say they wonder if their own health issues were caused by something in their homes.
Now federal investigators are trying to figure that out.
The Consumer Product Safety Commission was recently on post at the request of one of the families.
On Tuesday, Army CID brought them back out along with the EPA, CDC and HUD -- the team whose main focus elsewhere in the country has been on Chinese drywall, something Fort Bragg has ruled out -- will begin the most extensive testing to date to see if there is something in and around the homes that could have caused the deaths.
The Army will also review how Fort Bragg investigated the deaths.
After Lachlan Agee died, his mother says Fort Bragg conducted an autopsy against her family's wishes and religious beliefs.
She says higher ups gave her husband a hard time when she went searching for answers. She also says her current home on post has mold and water damage, and she says the housing manager at Bragg hasn't fixed it.
Agee says at this point she has very little faith in any investigation.
"I'm skeptical," she said.
Other families tell ABC11 that they do have more faith in the investigation, because it is independent and separate of anything that Fort Bragg has done so far.
They will have a long wait for answers, however, because the testing is supposed to take a few weeks with results not expected for several months.