A breakthrough medical trial allowed an adorable 3-year-old to hear his father for the very first time. Grayson Clamp is now officially the first child in the U.S. to have an auditory brain stem implant. Continue reading to see how he reacted when the chip was turned on.

Currently, there are about 1,000 people in the world who have received auditory brain stem implants, which were first used by humans in 1979. Grayson’s parents tried just about everything to help their deaf 3-year-old son hear, but turned to an untested method that had never before been used on children in the United States: an ‘auditory brain stem implant.’ After the chip was implanted, Grayson – who was adopted by the Clamps as a newborn after he was placed in foster care – could hear for the first time in his life.