A fire broke out in a Chicago apartment where three young children were home alone Wednesday night, but miraculously, all three survived. A neighbor pulled a mattress out beneath the third-floor window, and an 8-year-old girl jumped out and landed on it, hurting her ankle, ABC 7 reports. Her younger brothers, ages 4 and 2, were rescued by firefighters. The 4-year-old was about to jump when firefighters arrived and rescued him via ladder, CBS Chicago reports. All three are in serious condition at a nearby hospital. The children's mother says she was at work at the time and someone was supposed to be watching the kids; no one is currently in custody. Authorities say a stove burner was on, and the fire started in the kitchen. (More Chicago stories.)