I have a 27 year old sister whose behavior has changed dramatically over the past two years and especially over the past six months. Great declines in her interpersonal life as well as orientation. She obviously has down's syndrome. Professionals want to admit her to a psychiatric ward of a state hospital for evaluation purposes. I disagree, as a social worker and family member. My sister and her guardian, my father, live in a state known for its lack of social service or psychological savvy. Is dementia a possibility this young? I need a professional or someone who has had this experience with a loved one with down's to respond. - Desperate and in need of prompt reply.