A child sleeping in a Spokane Valley apartment was awoken by the sound of a smoke alarm going off early Thursday morning. The boy then woke the rest of his family-- an adult and another child. The family safely got out of the apartment and called 911. Spokane Valley firefighters arrived to the 7000 block of E. 2nd Ave. and found smoke and flames coming out of the back of the builiding. A total of 12 fire vehicles and more than 31 fire department personnel worked to put the fire out. A fire investigator is still working to figure out what caused it, but firefighters are crediting the working smoke alarm and the little boy for keeping everyone safe. According to Spokane Valley Fire, the family had just changed the batteries in their smoke alarms earlier that day when their apartment complex lost power.