The disappearance of Heidi Seeman in August 1990 launched one of the largest searches for a missing person in U.S. history.
Thousands of volunteers spent 21 days looking for the 11-year-old girl who vanished into thin air on a sunny Saturday morning as she walked home from a sleepover at a friend's house.
"She was less than a mile away from home," said Heidi's older sister, Heather Seeman. "Her friend Whitney walked her halfway home and by the time Whitney got back to her street and turned around, Heidi was gone."
The massive search effort covered 1,200 miles over the course of 21 days. The search came to a sad conclusion on Aug. 25, 1990, when Heidi's body was discovered in trash bags in a field near Wimberly.
While police have had suspects over the years, no one has ever been charged for the crime.
The Seeman family remains in contact with detectives at the San Antonio Police Department and the Texas Rangers. Tips are still called in and investigated.
"All of the efforts so far have failed to produce a suspect and a closure to the case," Seeman said.
Heidi's tragic death has had a lasting legacy in San Antonio and across the nation.
The Heidi Search Center, which was started to find Heidi, has taken on nearly 4,000 cases of missing children and adults over the past 22 years. They have a 98.1 percent recovery rate.
This year alone, the search center has been involved in 56 cases. Only five of them remain open.
"She's the reason we are all here," said Alisa Reynolds. "I believe she has created a beautiful legacy. We believe that we have a huge impact on our missing family's loved ones and bringing them home."
The center provides free resources to the families of the missing including search teams and flyers. They also offer free educational programs to parents in an effort to prevent child abductions, most of which could be prevented with proper supervision.
"(A total of) 77 percent of kids who are abducted are unsupervised," Reynolds said. "We need to stop child abductions. We need to stop child predators and people need to help us out with that. We can't do it alone."
In honor of what would have been Heidi's 34th birthday, the Heidi Search Center is hosting a birthday party for her Friday night. The public is invited to join friends, family and volunteers for a potluck dinner from 6 p.m. to 8 p.m. at the Heidi Search Center located at 4115 Naco Perrin Boulevard.
As she wonders what Heidi's life would have been like had lived to see her 34th birthday, Heather Seeman holds out hope police will someday find the person who killed Heidi and finally bring them to justice.
"All it's going to take is for someone that hasn't come forward yet that saw something to come forward," Seeman said. "She was my only sister and I still miss her every day."