MILLBROOK — A Millbrook man has pleaded guilty to first-degree manslaughter in connection with the 2021 killing of his teenage sister inside their family home, Dutchess County District Attorney Anthony Parisi announced Thursday. Mark Dedaj, 34, pleaded guilty in Dutchess County Court to a Class B felony, admitting that he caused the death of his 17-year-old sister, Maureen Nelson-Lanzi, by holding her face down into a pillow on a bed until she suffocated. The incident occurred on Sept.