According to reports, Sierra, 33, was scheduled to be on a plane back to the U.S. on Jan. 22, but never showed up for her flight home.
Sarai's husband, Steven Sierra, and her brother, David Jimenez, are reportedly en route to Turkey and scheduled to arrive there Monday afternoon. The two are set to meet with local officials and media to help strengthen the search, ABC News reports.
Sierra is an avid photographer who reportedly went ahead with the Jan. 7 trip after a friend had to cancel. According to her husband, as cited by ABC News, Sierra kept in contact with her family throughout the trip.
"It was her first time outside of the United States, and every day while she was there she pretty much kept in contact with us, letting us know what she was up to, where she was going, whether it be through texting or whether it be through video chat, she was touching base with us," Steven Sierra said.
When Steven Sierra arrived at Newark Liberty International Airport in New Jersey, the husband came to find that Sarai Sierra wasn't on board her scheduled flight.
After calling United Airlines, it was revealed that his wife had never boarded the flight home.
Steven Sierra told ABC News that a further investigation revealed that his wife had left her passport, clothes, phone charger and medical cards in her room at a hostel in Beyoglu, Turkey.
The U.S. Embassy in Turkey and the Turkish National Police are involved in the investigation, WABC reported.
"They've been keeping us posted, from my understanding they've been looking into hospitals and sending out word to police stations over there," Steven Sierra told the news outlet. "Maybe she's, you know, locked up, so they are doing what they can."
Sierra, who met her husband in a church youth group, is the mother of two boys, ages 11 and 9.