A 3-year-old North Carolina boy born without hearing nerves in his ears heard his dad\'s voice for the first time after a new medical procedure, officials say. Grayson Clamps of Charlotte underwent an 8-hour surgery at the UNC Hospitals in Chapel Hill, N.C., and received an auditory brain stem implant last month in the first operation of its kind in the United States, CNN reported Friday. Surgeons inserted a microchip on his brain stem at the brain\'s sound processing center, bypassing his ears. In a video, Grayson can be seen hearing his father\'s voice for the first time, saying \"Daddy loves you,\" and responding with a nod, KSFY-TV, Sioux Falls, Iowa, reported. \"Overwhelmed, joy, relief, excitement,\" Grayson\'s mother, Nicole Clamps, said of the moment. \"Before this there was no hope. This can change his life.\"