Simonds was one of several people who helped propose the idea of an alert system for missing children, a plan that eventually bore Amber's name.
Ernie Allen, the president and CEO of the National Center for Missing & Exploited Children, said he believes there may be "no greater legacy than that of Amber Hagerman."
"Amber's legacy is really remarkable if you look at what has happened and the lives that have been touched because one little girl lived and died -- it's pretty inspiring," Allen said.
Since 1996, according to statistics, there have been 495 successful recoveries thanks to Amber Alerts, which now exist in all 50 states. Allen said the program is even expected to grow internationally.
Amber Alerts, some of which can now be sent to the cell phones of people who sign up to receive notifications, are only issued when several criteria are met. The missing child must be younger than 18 and believed to be in imminent danger.
Officials must also have information such as a car model or a description of the abductor to provide in the alert, and authorities must be certain that the child has been abducted by a stranger (in some states, this provision is extended to include family members).
Had an alert of this kind been around at the time of Amber's disappearance, her mother believes she might have been rescued.
"I always said that if the Amber Alert saved one child's life I'd be satisfied, and I am, but I just wish there was something like [this] when Amber went missing," Norris said.
But Allen recognizes that there is still work to be done and that "tragic cases like Amber's" still occur, such as the recent case of 7-year-old Somer Thompson in Orange Park, Fla.
Thompson vanished on her walk home from school and was found dead a few days later in a Georgia landfill. As with Amber's case, nobody has been arrested in the abduction and murder.
Amber's mother said she sympathizes with parents like her and offered words of advice to the Thompson family.
"I'd tell them don't give up hope and keep fighting for your baby," Norris said. "If people don't catch the bad person, God will take care of him.
"Have faith, and have hope."