The number of infants that have died in a four-year span at Fort Bragg reached 12 last week, when the Army announced another infant had mysteriously died while living in post housing, The News & Observer reports.

The latest death was a boy, 4 months old, with no obvious illness, who seemed fine one minute on the morning of Feb. 24, and not breathing the next.

The case was especially eerie to Pearline Sculley, whose own son, Jaden Willis, was 2 months old when he died suddenly in 2007. Sculley still doesn’t know why.

According to the paper, the Army says it doesn't know, either, why 12 babies have died in four years, beginning with Jaden. An investigation of more than six months that included reviews of the children's medical records and autopsy reports -- and hundreds of environmental tests at the homes where some of the families lived -- failed to find a common cause.

Though the military can't say what killed the children, it is confident what didn't: Army housing, though three of the babies, including Jaden, lived at different times in the same townhouse on the North Carolina base.

Army officials have reportedly said the deaths fall within normal infant mortality rates, which count deaths of all causes among children less than a year old. Army figures are difficult to independently confirm. Mothers living on post may give birth at Fort Bragg's Womack Army Medical Center, or at a hospital off base.

The Army has said the average infant mortality rate from 2007 to 2009 for base residents at Fort Bragg was 5.3 deaths per 1,000 births. North Carolina's rate for 2009 was 7.9, the lowest in the state's history. For Cumberland County, where most of Fort Bragg's off-post population lives, the rate was 9.5 in 2009.

About 6,200 families, constituting about 18,000 people, live on Fort Bragg, in addition to about 45,000 single soldiers.

In discussing the infant deaths, Bragg officials have reminded parents to place babies on their backs to sleep and take other precautions to prevent sudden infant death syndrome.

"Multiple independent tests on the homes have identified no structural or environmental issues that would have caused these unfortunate deaths," Col. Michael P. Whetston, spokesman for the base, said last week. "We certainly wouldn't put soldiers [or] family members in quarters that are not safe and would take immediate actions if any of the test results indicated a potential environmental risk."

Click to read the full story on infant deaths at Fort Bragg at newsobserver.com