RecruitingDevice studysTMS Combined With CIMT and taVNS In Infants With HemiplegiaPreterm and term infants with brain injury frequently have delayed motor skills, and one hand and arm may become stronger than the other, which can signal early cerebral palsy. A new treatment, transcutaneous vagus nerve stimulation (taVNS), boosts specific brain circuits and may improve function when paired with intensive motor activities. This study will test taVNS-paired constraint induced movement therapy in infants who have greater weakness on one side and determine if a single pulse of transcranial brain stimulation over the motor area can cause a measurable movement of the hand or thumb, and indicate which infants can benefit from 40h taVNS-paired CIMT.