A six-year-old Columbia girl is being called a hero after alerting her mom to fire in an adjacent apartment.Columbia firefighters were called to the family's duplex located at 903 West 7th Street Friday morning after little Ava Brown smelled smoke and heard a smoke detector next door. "She screamed for me and said, ‘Mom I can hear an alarm going off next door,'" mother Toni Brown said. Brown quickly called 911.The apartment was not occupied, but new tenants, Demetrius Williams and his family, had already moved in their belongings.The fire started in a laundry basket filled with clothes. Investigators are not sure why. A wall heater was a few feet away."It was only a little basket. A whole bunch of bags and baby clothes were around it, but none of it caught on fire," Williams said. Firefighters were able to quickly put out the flames. There was no damage to the apartment.Williams told Nashville's News 2 he is thankful for the little girl's quick thinking."She is a hero in my book. She saved everything we own," he said, adding, "I'm glad she did because it could have been real bad. We could have lost everything before we even got in here."Williams has a newborn daughter and all of her baby supplies and clothing were already in the home.Brown added that she and Ava have talked about in the event of fire and that she recently learned about fire danger at school. "I'm very proud. I put it all over Facebook and I went to Opry Mills and bought her a bear for it," she said. "She's just a wonderful girl and a hero to me." The cause of the fire remains under investigation.