Deafness One Ear

The goal of this clinical trial is to investigate the safety and effectiveness of cochlear implantation in infants and toddlers with single-sided deafness. The main questions it aims to answer are: * Are cochlear implants an effective treatment of single-sided deafness in infants and toddlers? * Are cochlear implants a safe treatment for single-sided deafness in infants and toddlers? Participants will receive a cochlear implant and be followed until they are five years old. During those five years, the investigators will program the device and monitor auditory development. Children will be asked to: * Undergo cochlear implantation * Wear their cochlear implant processor whenever they are awake. * Participate in traditional hearing tests * Participate in traditional hearing testing * Participate in localization testing * Participate in hearing in noise testing * Participate in word recognition testing * Participate in speech, language, and educational evaluations The researchers will compare results to children with typical hearing in both ears and children with single-sided deafness who have not received an implant to observe any differences between the groups.