A Florida woman celebrating her birthday in Costa Rica disappears

A Florida woman on a birthday trip to Costa Rica disappeared last week under circumstances her family had described as suspicious.

Carla Stefaniak, of Hallandale Beach, Florida, went to Central America with her sister-in-law to celebrate Stefaniak's 36th birthday, said his brother, Mario Caicedo, during an interview Sunday.

Stefaniak recorded his return flight on November 28th. at some point within 24 hours of leaving. But she showed up to fly, he told NBC News.

"She was ready to go home, but she did not do it," Caicedo said. "That means someone kidnapped or kidnapped her."

Caicedo said that the Costa Rican police organization Organismo de Investigación Judicial was investigating the disappearance of Stefaniak. The agency did not immediately respond to a request for comment.

Caicedo said that his family had also been in contact with the United States Embassy in Costa Rica.

Stefaniak intended to leave the day after his sister-in-law's flight, according to a chronology of the last day spent by Stefaniak in Costa Rica at NBC News. The chronology shows that Stefaniak dropped off her sister-in-law and rental car at the San Jose airport on November 27 before visiting the city with a Uber driver.

After Stefaniak returned to Airbnb where she was staying that night, she posted a message on Whatsapp saying that there was heavy rain. The Airbnb list seems to have been deleted since.

"The electricity went out," she wrote at the time, according to schedule. "Super fragmentary."

At a FaceTime call with a friend, Stefaniak said that she could ask an Airbnb security officer to buy water at because of the storm, indicates the chronology.

She was on WhatsApp at 8 years old. : 8 pm, her phone died at 9 pm and she has not been online since.

Stefaniak, the insurer selling insurance in Hallandale Beach, north of Miami, is one of four siblings, Caicedo said. He described it as optimistic and social – the kind of person who would have checked all birthday messages posted on social media.

"She never went back online to check all her birthday wishes," he said. "It's still one thing that tells us that she's been kidnapped."