Crawford County Sheriff Tim Wilkerson said two children, ages 3 and 8, were among the dead, reported WDRB-TV, Louisville, Ky.
Two half-brothers and the girlfriend of one of the brothers also died in the fire, which started shortly after midnight in the town of Sulphur.
The 8-year-old was the daughter of one of the men and the 3-year-old was the woman's son.
Fire officials said the wood stove blamed for the fire appeared to be heating the home.
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