When a person is looking for a way to communicate in alternative ways, they need to find something that really works for them. They need to try to find a voice that sounds natural. They want to try to find a way to be efficient. They want to be able to communicate as normally as possible, even though they're not using their biological voice.
As your child with CP is becoming a teenager, there are a couple of things you may want to think about.
Cerebral Palsy affects body movement, muscle control, muscle coordination, muscle tone, reflex, posture and balance. Depending on the part of the brain that is injured depends on how someone’s muscle tone will be effected. For people with spastic CP they have increased muscle tone because of the part of the brain that's injured. If causes very tight muscles which in turn effects the movement of the joints and of the limbs. For others who have dyskinetic CP they lose the ability to have voluntary control over their muscles, and they can have jerky and uncontrolled movement patterns.