"Is Kristen alive?" her mother, Debbie asked. "I don't know."
Sunday, her family and friends in Charlotte dedicated a red maple tree to the young woman, who disappeared after she left her job at a San Francisco coffee house.
Modaferri finished her freshman year at N.C. State, studying industrial design. She moved to California temporarily to take summer courses at the University of California-Berkeley. She got a job at a coffeehouse in San Francisco's financial district.
The day before classes were supposed to start, someone saw Modaferri leave the coffeehouse.
But no one has seen her since.
Her family has traveled to San Francisco a dozen times. They say they will never give up hope.
Sunday, the family was at Providence High School, Modaferri's alma mater. At 3 p.m., they said another prayer and honored Kristen.
The Modafferis were surrounded by relatives and friends, Kristen's father said he is grateful for the continued love and support.
"Without that, I think you wind up feeling down at times," Bob Modaferri said, "thinking how long we keep on doing this."
The family hoped that by putting Kristen's name out there, somebody will remember something.
The Modafferis also work with other families of missing adults. They believe the publicity around events like the tree planting, will help their daughter's search.
"We still hope that at some point, we will be able to find our daughter, too," Bob Modaferri said.
The Modafferis crusaded for a new federal law to help parents searching for missing adults. It is appropriately called
WRAL Revisits Local Missing Persons Cases