“Can you say hi? He’s saying something!” For most new parents, that’s an interaction—you get the baby’s attention, and the baby babbles back—that is expected to happen. For Sierra, that never happened with her son, Travis. Born six weeks early, Travis spent about a week in the NICU. To get out of the NICU, he had to pass a newborn hearing test. Only Travis didn’t pass. Initially, Sierra and her husband were told that it likely was something simp…