Late last year, a male day care employee named "Darryl" followed a 4-year-old boy into the bathroom of a First Hill day care center, sexually assaulted the boy, then warned him not to say a word, court papers say. But several months later, the boy did -- telling his mother, and later a social worker, about the encounter with the man at Our Place Daycare on East Spring Street. "He said he's gonna kill me if I tell," court papers say the boy said of his alleged assailant. Yesterday, authorities said the boy's graphic account, detailed in court papers, led...