Everlyse Cabrera 2 1/2-year-old girl vanished May 15 while in care of Manuel and Vilma Carrascal

The former foster parents of Everlyse Cabrera have maintained months of public silence since they reported in June that the girl was missing.

In newly filed federal court documents that respond to a civil lawsuit by the toddler's birth parents, foster parents Manuel and Vilma Carrascal deny any wrongdoing.

The documents lay responsibility for Everlyse's plight on her birth parents, Marlena Olivas and Ernesto Cabrera, saying they "did not exercise ordinary care, caution or prudence for the protection of their own child's wellbeing."

"They both love children," said attorney E. Brent Bryson, who represents the Carrascals. "They feel horrible about what happened. But they did not cause any injuries to this child."

Everlyse disappeared while in the care of the Carrascals, who told North Las Vegas police that the girl had let herself out of the house during the night and wandered away. The girl, who was 21/2, was not seen by anyone outside the foster family after May 15. Searches for Everlyse by police and volunteers have been fruitless.

Police also have been frustrated by a lack of leads in the case, which so far is being treated as a missing-persons investigation and not a criminal investigation. However, police spokesman Tim Bedwell has said the disappearance of Everlyse is clearly more than a missing-persons case.

The lack of progress in the police investigation prompted the birth parents to file a civil lawsuit in September, seeking accountability and information regarding the supervision of their daughter while in the custody of Clark County officials.

In addition to the Carrascals, the lawsuit targets the county Department of Family Services and staff members involved in the girl's case.

Melvin Balane, the Carrascals' son and owner of the North Las Vegas home where the girl disappeared, also is named in the lawsuit and is represented by Bryson.

"My clients want whoever is at fault to be punished for what they've done," said attorney Greg Mills, counsel for Olivas and Cabrera.

The lawsuit was filed in Clark County District Court but has been transferred to U.S. District Court because it involves questions about whether the civil rights of the birth parents were violated.

Mills said Friday that language in the foster family's response to the lawsuit is standard for such documents, but that it makes "absolutely no sense" to blame the birth parents for something that happened when they did not have legal custody of their child.

"For an individual who doesn't deal in the law, that language is going to be offensive," Mills said. "My clients are going to find it offensive."

Mills said he plans to proceed with the case as quickly as possible and will turn over any evidence to police to aid their investigation.

Bryson said the Carrascals have been wrongly portrayed by police and the media as uncooperative. Family members gave lengthy interviews to police officers when Everlyse went missing and consented to a thorough search of their home, Bryson said.

While they've been criticized for not participating in the initial search for Everlyse in their neighborhood, Bryson said, the reason they did not was that police had asked them to remain in the house.

"The community has a false perception of my clients," Bryson said, adding that hostility faced by the Carrascals caused them to leave their home for a short period and take up residence in a hotel.

The Carrascals stopped cooperating with police when the questioning went from investigatory in tone to accusatory, he said. They responded to that the way most people would, exercising their rights and retaining an attorney, Bryson said.

"Right now, they feel like a lynch mob is ready to come and string them up," Bryson said. "They feel that's how the community views them now."

Everlyse's disappearance punctuates ongoing state and federal inquiries into the shortcomings and failures of the county's child welfare system. A report commissioned by the state found Clark County was underreporting and failing to investigate child deaths that may have been related to abuse or neglect.

In addition, the functions of Family Services have been called into question by several high-profile incidents involving children in county care.

Melanie Ochs, foster mother of Baby Boy Charles, has been charged with murder in the August death of the infant, who suffered severe head trauma.

The death of 15-month-old Joshua Sharp while in custody at Child Haven, the county's emergency shelter, also remains under investigation.

In addition to the Cabrera lawsuit, the county is facing legal action brought by the nonprofit California-based National Center for Youth Law. The lawsuit alleges that the county has endangered children by placing them in unsafe environments without adequate supervision.