ORLANDO, Fla. — Orange County investigators are trying to piece together the timeline of events that led up to a mother being arrested at Winnie Palmer Hospital in Orlando, with her 11-year-old daughter stabbed to death in the woman's car.

Rosa Alcides Rivera, 28, is being held in the Orange County Jail on a first-degree murder charge.

Investigators say the mother drove to Winnie Palmer Hospital in Orlando on Sunday morning with her daughter, Aleyda, dead in the passenger seat.

During a news conference Monday, Sheriff John Mina said Rivera had stabbed her daughter several times, then drove around with her injured daughter in the car for several hours, before taking her to the hospital. 

Mina said investigators believe Rivera stabbed Aleyda in the car and drove her around until she eventually died. 

In the course of that trip, she visited a home on Citadel Drive twice that day, with Aleyda in the car. 

"She did go to the address on Citadel. There was some discussion with the folks inside, some accusations, at one point left, and then did come back," Mina said.

Deputies said Rivera then went to Winnie Palmer and tried to get hospital staff to help Aleyda.

"My baby is gone," Rivera is heard saying on officer-worn body camera video, according to an Orange County arrest affidavit.

Investigators say that's when the woman became combative and pulled out a knife.

The hospital was put on a brief lockdown.

Orlando Health security and officers restrained her, and the incident caused some chaos for those at the hospital on Sunday.

According to the arrest report, when detectives confronted Rivera with testimony that contradicted her initial statements, she admitted to killing her daughter.

The report says Rivera thought her daughter was having sex with men because she smiled "different."

But investigators are now wondering if that statement was true.

"Our investigation revealed that Rosa Rivera killed her daughter because she wanted to prevent her from having sexual relations with men, but we believe that part of the investigation is unfounded," said Mina on Monday. "We are looking into that, but don't believe it to be credible, although we are still continuing the investigation."stabbing thought her daughter was in heaven.

Investigators said the girl's body had 15 stab wounds.

"(She was) a beautiful little girl like any other 12-, 13-year-old girl, beautiful. Nothing wrong with her... She wasn’t a bad kid," said Bianca Fernandez, who identified herself as a relative.

"She’d go to Disney all the time. Her grandmother did everything for them. But Rosa... We don’t know why she did what she did. It wasn't like she was struggling," Fernandez said.

The Orange County Sheriff's Office took over the investigation from Orlando Police officers after they determined that the initial incident occurred in its jurisdiction.

Rivera is not eligible for bond. She didn't make an initial appearance in front of a judge Monday afternoon at the Orange County Jail, but officials didn't say why.

Mina says there is no indication of prior abuse or issues with Rivera. 

Mina said this was another tragic example of domestic violence in the community, and urged residents to call the authorities if they see something.

"I think the message is that domestic violence continues to happen, not only in this community obviously, across the nation," Mina said. "But people see things or notice things, they need to call the authorities so we can get them the proper services and you know, stop these tragedies before they happen."

If you know of a domestic violence situation in your community, you can call the Florida Domestic Violence Hotline at 1-800-500-1119.

Aleyda Rivera a few years ago. (Courtesy of family)
Aleyda Rivera a few years ago. (Courtesy of family)