Valpeoz, 71, conducts himself with relentless force, but his eyes and the weight he's lost reveal his exhaustion. When he talks about his daughter -- his "Carly," his "Carlita" -- his husky, deep voice breaks into sobs.
For nearly six months he has traveled to nearly a dozen small towns in a remote region of the Peruvian Andes called the Sacred Valley. He takes flyers with his daughter's face printed on them and walks from house to house, interviewing anyone who might have seen her. Living on his savings, money from his son and some GoFundMe
donations, he's been staying in small hotel rooms and trying to spend as little as possible on food and toiletries.
Carla was on her way to an Inca archaeological site near Cusco on December 12 when she vanished and her family's lives turned upside down.
Her father has traveled across mountains, walked through massive cornfields and searched remote caves looking for her. He's developed relationships with the local police, and even embedded with them to search suspected drug houses.
Along with his son, he has tracked down people who met Carla before she vanished, found the backpack that she left behind at a hostel, requested surveillance footage and tried to request cell phone tower data, only to learn that previous police requests were never completed.
"People need to understand that if they suffer a tragedy like my family has been suffering, they need to know to be prepared for the worst, that they need to take matters in their own hands," Carlos Jr. said.
While the State Department has declined to share exact numbers on how many Americans have gone missing abroad in the past five years, stories of US citizens who vanish in a foreign country have recently made headlines. News outlets have covered the last known moments of a New York couple
that vanished and was later found