The typical cognitive assessments that are used for children require them to be able to use their hands to point to pictures or hold puzzle pieces.
For a child with CP learning to move, the really important things to remember are that the child should always be active.
A speech language pathologist is someone who is trained in working with kids and adults. Everything from working with articulation errors and correcting things to what I do, which is working with people with profound physical impairments and getting them augmentative communication strategies.