Child Prodigy Poet Dies of Muscular Dystrophy Wed Jun 23, 2:50 AM ET WASHINGTON (Reuters) - Mattie Stepanek, 13-year-old poet and advocate for muscular dystrophy patients, died in Washington on Tuesday of a rare form of the disease, a hospital statement said. Stepanek, of Rockville, Maryland, began writing poetry at the age of three and became a national celebrity in 2001 after publication of "Heartsongs," a volume of inspirational poems. It was the first of five books of poetry he had published and the first to be listed on The New York Times best-seller list. "Mattie loved to be referred...