Several neighbors had voiced concerns about an older man living just down the street, known as "Grandpa Charley," who they say often took little girls for rides on his bicycle. When police went to question him they say they discovered child pornography on his computer.
But further investigation cleared Grandpa Charley of any connection to Somer's murder. He has pleaded not guilty to child pornography charges. And within days police had turned their attention to another man who lived closer to Somer's school. His name is Richard Corpus, a 55-year-old handyman who works out of his home and spends a lot of time with kids.
"If I can't have kids, then I'll have somebody else's to play with, you know? I've got lots of kids that pass by," Corpus said.
ABC's "20/20" first met Corpus a few weeks after Somer was killed, standing at the corner near his house. He was greeting children on their way to school. Corpus had just gotten a new puppy and was carrying the animal inside his vest.
"I still will go out and greet kids and let them pet my little dog 'cause I think it brings happiness to the kids in the neighborhood," he said.
Corpus said he used to find Somer with her face pressed up against his chain link fence.
"Just so the dog will go and lick her face, you know? Somebody could have probably lured her very easily," said Corpus.
Over the next month police honed in on Corpus. He claims they seized his computers and monitored his calls.
"I can tell you this, every time the police walk in my house I start shaking," he said.
He said police even traveled to other states to question his sisters about his past. And that they gave him a polygraph test which he acknowledges he failed.
"They said that I failed one of them," Corpus said. "But if you sit in front with your glasses off staring a wall, I guess you do get dizzy after a while."
There is only one house between the vacant property where Somer was last seen and the corner where a crossing guard said he never saw Somer pass by. It is the house where Richard Corpus lives.
"I'm not a predator. But I can imagine, how this happened," Corpus said. "One, I'm going to look for some kids that are stragglers. Number two, I'm going to look for a kid that is -- innocent. And I'm going to plan it."
But while police were eyeing Corpus, he said he was on the lookout for the killer -- and he kept a hangman's noose in the garage just in case.
"This is not a threat, this is a promise," he said, displaying the noose for ABC cameras. "And, if I could, I'd hang him up from a light post and leave him there just to show the rest of the sexual predators what will happen. This is how extreme I want to catch this killer."
But for all this bizarre behavior, was Corpus merely a distraction in the pursuit of Somer's killer?
The holidays arrived, yet they brought no comfort or peace for one mother. Diena Thompson still did not have a face to put on the monster who killed her little girl and threw her away in the trash.
"I have to know for my own peace of mind what happened to her," said Thompson at the time. "I think that, what I have built up in my mind can't be any worse than what they're going to tell me."