Eighteen-year-old Kristen Modafferi, of Charlotte, was a sophomore when she vanished without a trace on June 23, 1997 in the San Francisco Bay area where she was going to summer school at the University of California at Berkeley.
Her family is now pushing for a national information database on missing adults.
When Modafferi's parents first called the National Center for Missing and Exploited Children, they found out it only helps find children and Modafferi was considered an adult.
Earlier this month, N.C. State students collected signatures on a petition in hopes to change the way missing adult cases are handled. The students hope to found an organization that looks for missing adults, as well as missing children.