ONAWA, Iowa (AP) — A western Iowa woman charged with drowning her 15-month-old son has been formally charged with first-degree murder. The Monona County attorney’s office filed the charge against 24-year-old Ashley Cameron, of Onawa, on Thursday. She’s scheduled to be arraigned May 14th. Cameron is charged in the Feb. 11 death of Markis Dahms. She was arrested on April 18. Police say Cameron held the toddler under a running faucet in the bathtub in their home until he drowned. The boy was found dead after officers responded to an emergency call about a child who wasn’t breathing. An autopsy later determined the boy had drowned and his death was a homicide. Cameron is represented by the state public defender’s office in Sioux City.