Missing-persons investigators -- burdened by heavy caseloads, and with few leads and resources -- rely on volunteer groups like EquuSearch to do the exhaustive work of searching for victims.
A number of regular Texas EquuSearch volunteers are relatives of victims from past searches, the Houston Chronicle reported.
EquuSearch director Tim Miller lost his 16-year-old daughter in 1984. Seventeen months after she was missing, her body was found in tangled brush near her home.
Another volunteer looking for Jackson is Daryl Buggs, whose 12-year-old daughter, Teketria, disappeared in December. With the help of Hunter -- a search dog trained to seek out cadavers -- searchers found her body in the Brazos River.
Since EquuSearch was founded in 2000, more than 38,000 volunteers have participated in 551 searches -- including the search for missing Alabama teen Natalee Holloway in Aruba and 2004 tsunami victims in Sri Lanka. The group has recovered 54 bodies.
Jackson's father, Roderick Fountain, is in jail, charged with beating his son.