Around 8 a.m., fire crews were called to the 6400 block of Kelmscot Court in the Four Seasons subdivision off Fillyaw Road.
When they arrived, the blaze that appeared to have started in a shed attached to the family's duplex had spread. The adjoining duplex was not damaged.
Four children -- ages 11, 12, 14, and 16 -- were home alone when the fire broke out. They were not injured.
The Red Cross is currently helping the children and two adults find a new place to live.
The cause of the blaze has not been released.