A speech sound development chart shows normative data that identifies which particular speech sounds are used, on average, at what particular age.
There are many stuttering problems for people who stutter. People with an established stutter are aware of the negative effect of repetitions, prolongations, hesitations and blocks on their speech. Their stutter (stammer) may be accompanied by facial tics and uncontrolled body movements. Stuttering can lead to the avoidance of certain activities and to social isolation.