Multiple media outlets report the Charlotte family was rescued Sunday evening after a neighbor's carbon monoxide detector went off.
Upstairs neighbor Edward Kennedy said he called 911 after he realized where the smoke was coming from and knocked on their door without an answer.
Charlotte Fire Department Capt. Mark Basnight said the mother had been cooking vegetables on a charcoal grill inside.
Firefighters found the four inside, semiconscious and unable to move. The children were ages 10 and under.
Their condition at a Charlotte hospital was unknown.