A deaf boy has heard his dad for the first time this week thanks to an auditory brain stem implant.
The moment was captured on video and shows the three year old's amazing reactions as he hears for the first time.
The video of the beautiful event has since gone viral on the Internet with viewers around the world enjoying the special moment for young Grayson Clamp.
The three year old has been legally deaf since birth, after he was born without cochlear nerves - essentially auditory nerves that help transmit sound from the inner ear into the brain.
He has been able to communicate with sign language, but the moment of him hearing for the first time has melted hearts of hundreds of thousands of viewers.
As he hears for the first time the little boy makes a stunned look on his face and his jaw drops open. He then points at his father, clearly understanding that he was hearing his dad's voice for the first time.
The miracle was possible through the use of an auditory brain stem implant that doctors implanted into Grayson's head.
The boy's delighted mother has said, "He likes sound. He enjoys the stimulus, the input. He's curious, and he definitely enjoys it."
Previously a cochlear implant had failed, but doctors then tried the new brain stem implant technology, and it appears to have worked perfectly.
The technology involves a microchip being implanted into the brain, which helps the person to hear without cochlear nerves.
The boy's mother said, "We don't know exactly what it's like for him. We don't know exactly what he hears. His brain is still trying organize itself to use sound."
Here is the amazing video of the moment the young boy hears his father's voice for the first time: