Jan. 31, 2008  -- The mother of a 27-year-old woman accused of marrying at least five military men at bases across the country says her daughter suffers from a rare mental illness .

"This is somewhat of a shock, but I've been expecting this," Cindy Gibson told "Good Morning America" today about her daughter Shauna Keith's arrest. "For the last five or six years, I've gotten random calls from men saying, 'I think I am married to your daughter.'"

Gibson told "GMA" her daughter suffers from Munchausen syndrome, a disorder where a person tells fictitious stories about their health or background in order to gain sympathy and attention.

For now, Gibson's daughter sits in the Walton County Jail in Georgia where she faces bigamy and fraud charges. She was arrested earlier this month in South Carolina, where she was living with a Marine stationed at Parris Island. She is being held without bond because she is considered a flight risk.

Authorities count at least five marriages starting in 1999 to men stationed at bases from San Diego to North Carolina. Some of those marriages ended legally, but in others, she just left. Keith, who is currently pregnant, has three children, two of whom Gibson legally adopted.

Gibson blames her daughter's behavior on Munchausen syndrome, which is based in part, on a craving for attention. "People with factitious disorders act this way because of an inner need to be seen as ill or injured , " the Cleveland Clinic says about the condition on its Web site.

"If the world she's living in doesn't fit her needs, she creates another reality," said Gibson, who lives in Gresham, Ore.

Georgia authorities say that Keith's reality has included leaving her military husbands financially and emotionally devastated and abandoning at least three children to be raised without their mother. Walton County Sheriff's Office Detective Jim Mayes counts seven names, five different Social Security numbers and three dates of birth used by Keith since 1999.

At least three times, Mayes said, Keith has been married to two men at the same time.

Mayes began investigating Keith in early January, shortly after she was married to a staff sergeant Marine at a Christmas eve ceremony in Georgia.

Suspicious family members contacted police to report a possible fraud after they found a doctored license and other evidence of identity theft among Keith's belonging, Mayes told ABC News Wednesday.

On Jan. 4, a warrant was issued for Keith's arrest — her birth name is Shauna Marie McDonald. The next day, Keith was picked up in Beaufort County, S.C., just miles from the Parris Island Marine Corps base. She was staying with another Marine when authorities found her.

Keith waived extradition, according to Mayes, and was returned to Walton County Jan. 11.

During Mayes' investigation, which included interviews with Keith and conversations with Gibson, Mayes says a timeline emerged showing at least five marriages that began in 1999 when Keith married a Navy sailor based in San Diego.

Keith gave birth to her first child during that marriage, which ended in divorce. A California court, Mayes said, gave full custody of the child to the father.

Keith then reportedly married a member of the Air Force stationed at Fort Carson, Colo. She became pregnant during that marriage and the child was ultimately adopted by Gibson, Mayes said. That marriage was legally dissolved after Keith left the man.

In August 2006, Keith married again, this time to a soldier stationed at Fort Knox, Ky. Sometime around that date, Mayes said, she gave birth to a third child, whose father remains unclear. That child was also adopted by Keith's mother. Soon after, she left that husband without a divorce, Mayes said, adding that the soldier has continued to work to get military officials to annul his marriage to Keith.

Just months later, in January 2007, Keith allegedly married a fourth military man, this time someone met at Fort Riley, Kan. In that case, the Army soldier found out that Keith was still legally married to the third husband from Fort Knox and the Army annulled the marriage, Mayes said.

After that, Keith met her most recent husband, a Marine Corps staff sergeant stationed at Cherry Point, N.C. After talking online, they met and subsequently married in a civil ceremony Christmas eve in Walton County, Ga.

Authorities working with military investigators know that Keith never has been enlisted in the military. But Mayes said Keith had obtained an identity card issued to military spouses that provided her free access to move on and off bases.

Keith, who could face additional fraud charges, will be represented by a public defender.