Exclusive: Mother's Desperate Search for Somer's Killer

Diena Thompsom, mother of murdered Somer Thompson, speaks out.

ORANGE PARK, Fla., Nov. 9, 2009 — -- The nights are the worst. Diena Thompson's mind races. She struggles to fall asleep and wakes up confused. It takes a moment for reality to hit again.

"I keep thinking that she's going to come in and this is just a nightmare and I'm going to wake up," Thompson said in an interview with "Good Morning America" in the living room of her home Friday. "And she's just been at somebody's house spending the night."

But her daughter Somer is not coming home.

Three weeks ago Monday the 7-year-old was walking home from school with her older sister Abby and twin brother Samuel. Her mother was at work. And as usual, the children were to walk home together. Friends' parents would keep an eye on them.

"I know that Samuel had lagged behind talking to a friend," Diena Thompson told "GMA." "And Abby and Somer were together and that -- I'm not sure what happened. Somer got teased a lot. ... She ran ahead, and Abby just figured she'd catch up with her. And when she got to the second crossing guard Somer wasn't there."

Somer was last seen in front of a vacant house on a block she walked every day. Investigators found her body in a Georgia landfill two days later. Thompson does not know exactly how her daughter died. It was recommended that she not view the body.

Her grief is immeasurable. She is anxious and guilt-ridden. But she is speaking out now, at the three-week mark, because she wants the killer put on notice that they are still hunting, and she wants other parents to hear her words.

To date, investigators at the Clay County Sheriffs department in Jacksonville say they have pursued more than 3,000 leads. But still no arrests.

Over the weekend, authorities released sketches of two items that Somer had with her on the day she disappeared, which have never been recovered.

Police ask anyone who has seen the tote bag or zippered round lunch pail to call their tip line at (877) 227-6911.

Diena Thompson: Killer Would Be 'Lucky' to Be Caught By Cops Before Her

Friends of Thompson have also established a Web site, www.rememberingsomer.com, which is devoted to Somer's memory and the investigation.

"There's been amazing outpouring of support," said Thompson's lawyer, Michael Freed. "There's been a trust created to help Diena raise her surviving children in as normal a way as she can. And of course, there's opportunities to increase the reward which hopefully will be helpful as well. And, as Diena said, that really means a lot to her and to the family," he said.

"I can't imagine them not catching him," Thompson said. "That's my scariest ... I feel like there's a piece of broken glass in front of me. And I've got all the pieces to the broken glass except for this one, huge piece and that's to catch the monster who did this."

Thompson described Somer as a beautiful 7-year-old who always wanted to help, wanted to make people feel better.

"She just always wanted everybody to be happy with her. ... So sweet. Hugged everybody," she said. Somer routinely hugged the crossing guards she met on her route home from school.

The hard question Diena Thompson is now asking herself is whether someone might have taken advantage of that kindness. Investigators asked her if she thought Somer might willingly get into a car with a stranger.

"And to hear the word 'yes' come out of my mouth cut me," Thompson said.

Because there have been no arrests and the sheriffs department has not shared any concrete leads, Thompson worries that the killer may still be in the community.

"I've thought, 'Please don't let it be one of these people that's come around and hugged me and said how sorry they were.' I've thought, 'I wonder -- when we were doing the candlelight vigils if -- if he was out there," she said.

And if it turns out to be someone she knew?

"God have mercy on their soul. And they better be lucky that the Clay County Sheriff's Office is gonna get to 'em before I can."

Diena Thompson's Advice for Parents

It is a struggle to balance that anger with a mother's need to stay strong for her remaining children. Thompson said the ordeal has been especially hard on Somer's twin, Samuel.

They used to play in the pool together and race each other to see who could stay underwater the longest.

"We used to nickname her 'Grace' because she couldn't really walk and chew bubblegum at the same time," Thompson said of Somer.

She loved to dance, but she had no rhythm, Thompson said.

"She was just so wonderful. And you take it for granted. You never think you're gonna be sitting here," Thompson said. "And you have a lot of regret because you may have been too busy. And you weren't really busy. You were just too busy in your head. And I'll have to live with that, and that's hard."

She said she would tell other parents to be sure and tell their children they love them every day.

"It don't take but a couple seconds. And when you think you're too busy, really think about what you're saying you're too busy for. Because you don't want to live with this. That's what I regret. It's hard to live with regret and guilt," she said.

Diena understands acutely that the world's attention will move on. The flowers in her home are beginning to fade. The vigils that used to occur nightly have grown more infrequent.

But she is determined to continue the fight for justice.

"I know I'm not gonna let this monster win. I will be victorious in the end, and he will pay," she said. "We're gonna get him, and he will pay. And I hope he's scared."

Visit www.rememberingsomer.com for more information on the reward fund and family relief fund.

Police have asked that if you have any information about this case, contact the Clay County Sheriffs Department in Jacksonville, Fla. at (877) 227 - 6911 or the FBI.