Its been 18 years since Mikelle Biggs disappeared Jan. 2, 1999. Her sister, Kimber Biggs, was the last person to see her.
Mikelle is one of Arizona's 59 missing children in the National Institute of Justices Missing and Unidentified Persons System, a database under the U.S. Department of Justice.
Her case officially remains open today.
Her body never has been found.
No suspect ever has been identified.
No firm evidence of what happened to her has been uncovered.
There are theories and they have run the gamut, sending detectives chasing tips from Pennsylvania to Mexico. Theories of drug smugglers taking Mikelle to Mexico. Speculation that the ice-cream truck finally arrived on the block but accidentally hit her. Suppositions that a sexual predator, a neighbor, snatched her.
But they are only theories.