John Walsh’s son Callahan explains how his brother Adam's murder made him determined to catch ‘bad guys’

EXCLUSIVE: Callahan Walsh is determined to help families in need after his parents endured their own personal tragedy.

In 1981, his brother Adam Walsh was abducted from a Hollywood, Fla. shopping mall. The 6-year-old’s head was discovered two weeks later. His other remains were never found.

The horrific murder compelled patriarch John Walsh to become a victim’s rights advocate. He instituted the Adam Walsh Child Resource Center. He also co-founded the National Center for Missing and Exploited Children.

Then in 1988, the now-75-year-old launched a TV show titled "America’s Most Wanted," where viewers were told about crimes in the hopes of leading to an arrest. The series, which aired for 25 seasons before its cancellation in 2011, helped capture more than 1,100 criminals - including 17 on the FBI’s Ten Most Wanted List. It also aided in reuniting 43 missing children with their families.

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"I grew up in a family that celebrated Adam’s life," Walsh, 36, told Fox News. "I knew his favorite sports and movies. We celebrated his birthday. But at the same time, I watched my parents channel their anger over what happened to Adam, to make sure that Adam didn’t die in vain. They co-founded the National Center for Missing and Exploited Children, a place where I work today. It’s sort of my day job. It’s an organization that’s helped recover over 350,000 missing children."

"I grew up with my parents saying that if Adam’s song is to continue, then we must do the singing," Walsh shared. "And I’m trying to do that every day as a child advocate. I want to help get families the justice they deserve."

After "America’s Most Wanted" was canceled, it was briefly picked up by Lifetime. The series is now being revived with Elizabeth Vargas as its new host. John released a statement in January stating that capturing criminals and finding missing children was his life’s work and he was excited about and in support of the show’s revival. 

From 2019 until 2020, he served as executive producer for "In Pursuit with John Walsh." In August 2020, James Meese, who was convicted of raping two Michigan children, was arrested by federal agents in California where he had been hiding out. The 71-year-old’s arrest came months after the show profiled his case in March.

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As for Walsh, he’s hosting his own streaming special on discovery+ titled "In Pursuit: The Missing," where he actively investigates two mysterious disappearances while showcasing additional unsolved missing person cases from across the country.

In the series, Walsh traveled to Cape Coral, Fla. to learn about Lauren Dumolo, a 29-year-old single mother who was last seen at her apartment on June 20, 2020.

 He also traveled to Fort Lauderdale to further investigate the 2017 missing person case of Sophie Reeder, a 15-year-old who snuck out from her father’s home. During his exploration, Walsh focused on the dark web and the ongoing epidemic of human trafficking.

"These two cases have a lot of mystery surrounding them," Walsh explained. "Their families are desperate for answers, desperate to see their loved ones again. And we’re hoping that by providing the information to the public, harnessing the power of the public, we can provide answers to these families. Somebody out there holds the key that can unlock the door to justice in these cases. And we’re looking for those keys."

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"It’s so tragic for anybody that’s dealing with a missing person case," he continued. "You don’t know the whereabouts of your loved one. You don’t even know if they’re OK. You don’t know if they’re safe. It’s the worst thing that a family can go through. I can empathize with these families. But I also know it takes the public’s help to crack these cases. The public’s help can keep these investigations going."

Walsh is aware that when it comes to missing cases, families can lose hope with the passing of time. But speaking from personal experience, he has a message for them.

"We say to families, never give up hope," he said. "Keep beating that drum. Law enforcement has other cases that start mounting up. Other crimes occur. The media has other stories that they need to tell as well. But be the advocate. Be the voice for that missing loved one because they no longer have a voice. Keep that hope alive."

"You know at the center, we work on thousands of cases at any one time," he shared. "And we never stop searching for any of the missing children that are reported to the organization. We never give up hope because we know the families will never give up hope. And we’ve seen way too many long-term recoveries, like the Cleveland girls, Elizabeth Smart and Jaycee Dugard, to ever give up hope on any of our missing cases."

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Walsh pointed out that runaway cases can often be overlooked by the press because someone may have seemingly left home on their own. However, he said many young runaways end up in the open arms of child predators.

"The majority of children that are reported missing to the center are runaway children, many who don’t have a support system or individuals looking out for them," he said. "It’s an unfortunate scenario. But then we also see a lot of grooming and luring cases where a child is groomed, lured and manipulated from the home, which may have been the case for Sophie Reeder."

Walsh said there are two people who are especially proud of his work - his mother and father.

"My father has big shoes to fill," he reflected. "I’m just honored to continue both of their legacies, hunt down bad guys and find missing people with the public’s help. And my father is really my role model. I watched him go out and capture bad guys year and year while being an advocate to children in need. I’m privileged to say that I have a great father. And I’m trying to do the best I can to fill in those shoes."

"In Pursuit: The Missing" is currently available for streaming on discovery+. The Associated Press contributed to this report.