RecruitingBehavioural interventionSpeech Production Enhancement Using Augmentative Communication for KidsThe goal of this clinical trial is to learn if speech supplementation can improve speech intelligibility in children ages 7 to 17 years with cerebral palsy. The main questions it aims to answer are: * To what extent can speech supplementation improve intelligibility in children with CP compared with habitual speech produced without speech supplementation? * How much intelligibility change is necessary for meaningful improvement when children use speech supplementation strategies? Participants will: * complete speech and language assessments * complete a speech pre-test using habitual speech * learn a speech supplementation strategy with training from a speech-language pathologist * complete a speech post-test using the speech supplementation strategy * complete a speech repetition task where specific words are emphasized (emphatic stress) * use the previously learned speech supplementation strategy + emphasis on specific words while producing a set of sentences