(CBS) -- 12-year-old Annie Bourassa has come a long way since Marc and Phyllis-Ann welcomed her into their lives.
At just three years old, she was removed from the care of her biological mother over alleged substance abuse and neglect. The toll has been profound.
"At first, she was hitting and lashing out verbally, and yelling and screaming," said Phyllis-Ann.
Annie is living with reactive attachment disorder: a serious condition known as RAD, stemming from the severe neglect she suffered before she was adopted. Children with the condition find it difficult to build healthy relationships and attachments with new caregivers, even when they're showered with love.
"When you consider the trauma, and you consider what she went through, it's not something that's going to go away in a brief," Marc said.
Annie received years of treatment at Bridgewell, Massachusetts non-profit organization where doctor Jackie Devine is a psychologist.
"It often presents as extreme behavioral issues," she said.
Dr. Devine says she's seeing more and more children with RAD because of the current drug crisis. Those children require intensive therapy for trauma, and long-term stability.
The child needs to have healthy relationships and consistent relationships.
For Annie, that has been critical for her progress. Today, she's an outgoing sixth grader with a big heart.
"I want to help people with physical disabilities, and be there for them and help them," Annie said.