AUSTIN (KXAN) – A family is “desperately” searching for a couple that went missing while traveling through Mexico.  Frank Guzman, an University of Texas at Austin graduate student, and his wife Caroline Katba had planned to drive from Austin to Chile. Frank is working towards his Ph.D. in cultural anthropology and was headed to do fieldwork in Chile, his sister Liz Guzman said.  "They're just very open people. They're kind people -- kind, regular people who wanted to explore the world," Liz said.  Frank Guzman, a University of Texas at Austin graduate student, and his wife Caroline Katba went missing while driving through Mexico. (Courtesy Liz Guzman) "The first half of the trip [through Mexico] was supposed to be just vacation," she continued. "There was a goal [destination]– there was, and they didn't reach it." July 22 was the last day the Guzaman and Katba families received any communication from Caroline or Frank. Liz said the families believed the couple at the time was visiting Coatzacoalcos, a city in the Mexican state of Veracruz, when they lost contact. “Now everyone is extremely confused and desperate to find answers,” Liz said. “I've never felt this desperate for anything in my life.”  “We're at that point where whatever happened, we will accept the truth for what it is, whether that means that they come home or not. We just want to know what happened,” she continued.  Liz said she and her family have contacted authorities in the US and Mexico, but have not received information that might help paint a picture of what happened.  “I just plead for family and friends to just to share, share, share, and get the word over there to Coatzacoalcos," she said.