Go stand on a sidewalk and pay attention to the sounds. Traffic going by, people walking, birds chirping, brakes squealing.
They're all layers of sound many of us don't even notice, but three-year-old Grayson Clamp just started hearing them for the first time three weeks ago.
Grayson was born completely deaf. He's missing the cochlear nerves which act like a bridge in the ear. They help us process and hear sound.
His parents, Len and Nicole Clamp, wanted to help Grayson anyway they could. They tried a cochlear implant, which did not work.
Then they heard about a research trial for children at UNC Hospitals in Chapel Hill. Grayson is the first child in the United States to have what's called an "auditory brain stem implant."
A microchip implanted in his brain helps process and recognize sound which travels through tubes to his ear.
"We don't know exactly what it's like for him," said Grayson's mom, Nicole Clamp. "We don't know exactly what he hears. His brain is still trying organize itself to use sound."
She and Len say their job now is to teach Grayson how to process the sound.
When the device was installed and went active, Grayson heard his father's voice for the first time. Grayson's face lit up the room.
"It's been phenomenal for us," said his father, Len. They first met Grayson as a newborn in foster care. They adopted him as soon as they could.
The Clamps say they felt God's calling to help medically challenged children. They have given Grayson the gift of sound, but he has given them a gift as well.
Nicole says it's a thrill to see him play and watch how the world of sound is changing his life.