Multi-modal Neuroimaging in Children With Cerebral Palsy or Brachial Plexus Birth Palsy

Inclusion Criteria: Children with Cerebral Palsy should have: * An evaluation by a pediatric neurologist with a diagnosis of CP due to PV-WMI, * Absence of any genetic syndrome diagnosis, * No history of trauma or brain operation, * Classified as high-functioning (I or II) at the Gross Motor Function Classification System (GMFCS)32. Children with Brachial Plexus Birth Palsy should have: * An evaluation by a hand and upper extremity surgeon with a diagnosis of BPBP * May or may not have undergone primary microsurgical or secondary reconstructive operations prior to this study. Typically Developing children should have: * No history of neurological disorder or brain injury. Exclusion Criteria: Children will be excluded if they meet any of the follow criteria, determined via their medical and developmental history: * Having a hard time sitting still, * Presence of any metal implants, * Baclofen pumps, * History of traumatic brain injury or brain operation.