Mom Learns Her 2 Adopted Kids Were Exposed to Opioids in the Womb, Then Starts Group to Help Other Families (Exclusive)

"The world needs to know about them and their needs,” Theresa Harmon tells PEOPLE, “so they can meet their true, full potential"

• Theresa Harmon's two children both have neonatal abstinence syndrome, or NAS, as a result of being exposed to opioids in the womb

• Harmon started her group, To the Moon and Back, to help other families like hers navigate NAS, which affects a growing number of young people

• "The world needs to know about them and their needs," she says

Theresa Harmon calls herself an advocate for the unseen.

In 2017, she started To the Moon and Back, an advocacy organization to fight for the growing group of children and young adults nationwide who were exposed to opioids in the womb and who now live with a multisystem disorder called neonatal abstinence syndrome, or NAS.

NAS can present an array of physical, learning and behavioral health issues such as developmental delays and hyperactivity.

About 10,000 diagnoses were made between 2010 and 2017; the Centers for Disease Control and Prevention has calculated that there’s now one child born with NAS every 24 minutes.

Harmon, 45, says she was inspired by her own experiences to create her New England-based national support organization: She and husband Andy adopted the first of their two children — both have NAS — more than a decade ago.

"The world needs to know about them and their needs,” Harmon tells PEOPLE, “so they can meet their true, full potential."

Her older son has attention deficit hyperactivity disorder and high-functioning autism. He also has a food-intake disorder in which he struggles with the temperature, look and smell of food so has a difficult time obtaining proper nutrition.

Related: Daughter Born Dependent on Opioids Entered Foster Care While Mom Got Help. How They Reconnected Years Later (Exclusive)

Harmon says her children are “beautiful, smart, and amazing. They have so many wonderful strengths but also many struggles brought on by their in-utero exposure. I wanted them to have everything that they needed to succeed."

As her oldest son grew, his complicated behaviors ramped up.

“He was having regular meltdowns and the people you typically turn to for support — school, pediatrician, daycare — weren’t able to help,” says Harmon. She knew that if the professionals, including herself, with her background as a clinical social worker, couldn’t figure out what to do, other families must be struggling as well.

So, seven years ago, she planned a support group for families of opioid-exposed kids near her home in Plymouth, Mass., and people turned out en masse, voicing the same concerns about their kids.

“That’s how TTMAB was started,” she says, referring to her group. “We built off the unmet needs of our community and waited for the medical community to catch up with us.”

To the Moon and Back is a registered nonprofit that offers support to people across the country. More than 450 families participate in the organization’s public and private Facebook pages.

Harmon hosts online support groups for caregivers and in-person play groups and get-togethers. Members also host an annual conference for providers and families where they can learn about new research and interventions.

The group has been instrumental in helping to pass bills directing dollars to children born drug-dependent and prioritizing legislation that improves direct resources such as early intervention.

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The opioid epidemic, which began in earnest in the '90s, has been complicated and punitive for so many Americans — and its devastating toll, in deaths and in the disease of addiction, is well documented.

"Yet somehow we don’t hear about the long-term effects of in-utero opioid exposure on the kids. Money rarely goes to support them and yet so many are growing up with a myriad of struggles,” Harmon says. “These children deserve a spotlight beyond the neonatal period.”

She traces her energy and determination to her own life-and-death challenges as a two-time childhood cancer survivor.

“I spent most of my life fighting to stay alive — first from childhood cancer and then from the long-term effects into adulthood,” she says.

She says she grew up as one of the first generations of survivors of bone marrow transplants and adult-dosed chemo and radiation on a child: “People never knew what to expect of me, the same as children with NAS. I didn’t want them to have the ambiguity I had growing up.”

Related: Exposed to Drugs in the Womb, 20-Year-Old Now Following His Dream of Helping Others in Emergencies (Exclusive)

Harmon has high praise for the other parents in her group. “They are such warriors for their children. Many get so excited when they learn we are out here fighting for them and wish they knew about us sooner because they feel isolated and like they have been fighting on their own."

"Many share their stories of struggling, fighting and advocating — because they don’t feel supported by the medical and educational systems,” she adds.

Still, it’s the kids whom Harmon most appreciates.

“One of my favorite things is when families have discussed their child’s birth history with them, and when they attend our events we hear that the children immediately feel a sense of camaraderie and normalcy,” she says. “We know it helps them to know there are other kids just like them.”