Wahid Leeman, 20, has more than his share of challenges, including bipolar disorder, sickle cell anemia and ADHD. Physical and mental health symptoms appear due to drug exposure in utero.

Like many other young Americans, he was diagnosed at birth with neonatal abstinence syndrome (NAS), which occurs when a developing fetus is exposed to opioids and is born addicted to the substances.

Wahid’s biological mother was in and out of his life, oscillating between addiction and recovery, and died of an accidental overdose when Wahid was 14. “I wish she hadn’t done it,” she told PEOPLE in this week’s issue about her birth and the mother’s drug use. “But I feel like he did the best he could at the time.”

Wahid was adopted when he was 2 years old by Tammy Cutchen and Steve Leeman, who lived in a community off the coast of Maine. Tammy takes care of the family’s 11 children while Steve is a lobsterman. Both Wahid and one of his siblings share a diagnosis of NAS.

Tammy says Wahid’s path to adulthood has been a rocky one. “He has a lot of anger about his mother’s choices,” she says. He also has reactive attachment disorder, a combustible combination that dulls impulse control.

She says Wahid was incredibly destructive as a child, breaking down doors, punching walls and breaking windows. Once, when Wahid was 7, Tammy even tried jumping out of a car because she refused to stop for fast food.

“Raising Wahid was the hardest job I’ve ever had,” she adds. “I have no idea how we got through this.”

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Looking back, Tammy takes responsibility for amplifying some of Wahid’s outbursts because “I put him in situations and places that his system couldn’t handle, and then I blamed him for it.”

This realization informs how she and Steve raise her 8-year-old son, Cruz Leeman, who has similar behavioral symptoms as his brother. “We take great care to keep Cruz’s world as small as possible while still allowing him to have a variety of experiences,” says Tammy.

As a young adult, Wahid is aware of how impulse control issues can complicate his life, for example in long-term friendships. “It’s like if someone does something wrong, I interrupt them. “Or it could be something like wanting to tell someone something, but blasting their phone with calls and messages even if they don’t answer,” he says, and continues: “This can cause relationships and friendships to end. I can feel really really bad about this.

But Wahid’s symptoms at NAS do not overshadow his enthusiasm for life. He loves fishing and swimming, is a fan of reptiles (including day gecko Lizzy), and enjoys his food service job, “because I love money as much as other people.”

But securing his future is his most important duty. Wahid is studying to become an EMT at a local community college. He plans to complete his courses next year “to make myself fully employable in one of the major fire services.”

“My goal is to become a firefighter-paramedic,” he adds.

His mother believes that a career as a first responder could be very good for her son and give him the opportunity to use his different talents in a positive way. “He is very focused on the situations at hand and not distracted by emotion and chaos,” he says. “In an emergency, he would do the right thing to keep people safe.”

Tammy says she and Wahid share a remarkable bond. “Wahid is a special person,” he adds. “He worked really hard and overcame a lot.”

If you or someone you know is struggling with substance abuse, please contact the SAMHSA helpline at 1-800-662-HELP.