It all began when his mother read that children who stutter often find success through singing. So, she signed him up for lessons at Proline Music in Fairless Hills, Pa.
After he began to sing, his parents finally heard their son's voice.
"To hear his voice, we were like wow!" said his father, Wally. "It was really great."
Speech therapist Joe Donaher says when we talk, "We're thinking, organizing and formulating what we want to say at the same time we're producing it.
But, when singing, the words and rhythm are already there, making it easier for someone who stutters to sing fluently.
Still, what they didn't expect was Calvin's talent.
"You hardly ever see that kind of talent in this particular setting," said vocal coach Steve Burke of Proline Music.
"He can sing a high F over C 5, which is pretty amazing for anybody. I can only think of that note, I can't sing it."
Donaher says, in most cases, singing won't help with speech but it will help with confidence.
"When he feels better about himself, because he knows how skilled he is as a singer, that's going to carry over," Donaher said.
To find more information about the Intensive Stuttering Project at the Children's Hospital of Philadelphia call Joseph Donaher at 215-590-7637 or email Donaher@email.chop.edu
They also have a camp that runs from June 24, 2013 through June 28, 2013.
They are also looking for sponsors.