When Susan Butler found out her son, Collin Butler, was diagnosed with autism, she was heartbroken.

The news no parent wants to hear set her on a path to help Collin, as well as other kids like him, achieve what seemed impossible.

Susan brought Applied Behavioral Analysis (ABA), an effective way to treat young people with autism, to South Carolina, through the South Carolina Early Autism Project, which she started with Collin’s preschool teacher, Ann Eldridge, in 1996. The organization offers individualized research-based treatment to thousands of children and young adults from 20 months to 21 years old.

“To see the transformation of so many kids that we work with reminds me how far we’ve come as an organization,” Susan tells PEOPLE.

Collin, now 22, was your typical baby. He was all smiles one minute and hysterical the next.

Once he reached 14 months, things started to change. He lost words he once knew and began communicating less and less. Because he had trouble speaking, he would throw tantrums to get what he wanted.

“It was really hard for him because he was such a smart little fella and had so much potential,” Susan says.

Collin’s story
Susan took him to three different pediatricians in Sumter, South Carolina, where they lived at the time, before finally getting the diagnosis.

But there was still no solution and Susan was worried about Collin entering preschool.

She called UCLA, where doctors were making progress with ABA treatment. Butler and her husband, Joe Butler, were referred to a similar program out of Wisconsin – the Early Autism Project. After numerous calls, Dr. Sallows, head of the program, agreed to take Collin on as a workshop case.

“Susan and Ann were movers and shakers down in South Carolina and have really made a difference for the state,” Dr. Sallows tells PEOPLE. “Applied Behavioral Analysis treatment is the most powerful invention I know and was happy to find out that they were bringing the treatment there.”

During the summer of 1996, Dr. Sallows flew to South Carolina and started the program with Collin. On a Friday afternoon, Susan sat on her living room floor with Eldridge, four therapists, two babysitters and a speech therapist. They all watched as Dr. Sallows developed a special treatment specifically for Collin.

It was tough at first. Collin shouted and was physical toward Dr. Sallows. He would punch and dig his nails into his skin.

After evaluating Collin by asking him questions, Dr. Sallows learned what he was capable of and put together a custom treatment for him.

Once he entered preschool, Collin was placed in a special program that gave him the proper support to get him ready to transition into a regular classroom setting.

Eldridge recalls the difficulties while working with him. She would tell Susan that he was persistent when playing with toys and threw a fit when it was time to move onto the next activity. He was very aggressive and would bite and kick the teacher and other students.

“He was almost un-teachable,” Susan says.

Eldridge took the lead to make sure the skills he was learning from the treatment at home were getting implemented in the classroom and she started seeing a difference.

“The crossover was really critical for his success,” Eldridge tells PEOPLE.

She wasn’t the only one noticing. Other mothers were coming up to her and saying how they’ve noticed a big improvement in Collin. He was now making eye contact and saying hello.

Susan and Eldridge were feeling hopeful, that is until Collin’s 5k teacher went up to Susan and said, “Nothing short of a miracle will have Collin functioning in a work or educational environment.”

“I went home and cried and cried,” Susan says. “But then I pulled myself up and became more determined than ever to prove her wrong. I just saw so much future and such a bright little boy.”

He went from 5k, where he was going to school for a half day and then receiving 30-40 hours of treatment at home, to kindergarten, where he was starting to participate. Instead of stepping around him, his classmates started engaging him.

By the time third grade came around, he didn’t need any support or therapy.

Providing treatment to other children
As Collin made more progress, other mothers wanted to come see the program and some families even started moving to South Carolina so that their children could receive the treatment.

“When you get the diagnosis of autism, it feels very hopeless and discouraging, so when I initially began, I made my primary goal to help educate those on how the program worked,” Susan says.

She and Eldridge gave a speech at George Washington University in 2003 to a group of parents, educators and service providers. After Lorri Unumb, a professor at Charleston Law School, heard them speak, she decided to move her family to South Carolina to treat her son Ryan, but was disappointed to find out that insurance wouldn’t cover the treatment.

So Unumb, Susan and Eldridge banded together with other mothers in the state in 2005 to try to get an insurance mandate and Medicaid waiver passed. By 2007, they made it happen. Today, the insurance mandate pays $50,000 a year for treatment per child.

The South Carolina Early Autism Project is currently treating 700 kids and families are continuing to move there for the program.

Collin Butler graduating from University of South Carolina

Collin Butler graduating from University of South Carolina

“If my mom wasn’t determined to seek that treatment, I’d probably be under her care twenty-four/seven,” Collin tells PEOPLE.

Collin graduated from the University of South Carolina in December and plans to either go on to get his masters in linguistics or become a motivational speaker. He is fluent in 12 languages, all of which he is self-taught, so he’d like to travel the world sharing his story.

“It was a thrilling experience to be there to watch him receive his diploma after having worked with him from a young age,” Eldridge says. “Because of Collin my life has changed, and now I’ve had the opportunity to work with other children and I’m grateful for Collin for giving me that gift.”

Collin also recognized how far he’s come.

“For most people, graduating is a big achievement, but for a person with autism, that’s like really really special,” Collin says. “My mom certainly had a plan for me to prove to the world that people like me can go on to accomplish great things.”

Now, when he feels like he’s going to have a tantrum, he stops himself.

“I turn cartwheels over things most people take for granted,” Susan says. “I am so thankful that Collin taught me to appreciate everything he has been able to achieve.”