Police say a family member found the bodies of a 58-year-old man and his 69-year-old sister Tuesday evening. Their names were not released.
Emergency responders found a gas-powered generator running in a basement garage and an extension cord linked to appliances in the home.
The house, near 51st and Kimball in Kansas City, kansas was without power because of the winter storm.
Responders found carbon monoxide readings in the garage of 600 parts per million, far above what is considered dangerous.
Two small dogs also were found dead in the home.