Below 20 is considered extremely seriously retarded, and such individuals must rely on the help of others in all aspects of life. Are children with Down's more likely to strike others and be violently inclined?
廿以下屬極重度，學習能力有限，衣食住行方面也需仰賴他人協助。唐氏症的孩子會打人，有暴力傾向？