The Montgomery County Fire Department responded to a fire in the 16000 block of Long Valley Court around 2:30 a.m.
According to the fire marshal, an 18-month-old, 6-year-old and 93-year-old were killed in the fire.
Firefighters said seven people were trapped inside of the single-story home. According to investigators, the fire started in the kitchen area of the home and spread to the living room and attic.
A neighbor busted through a window to rescue a 5-year-old and 7-year-old who were trying to escape through a window.
Officials said the father received burns and lacerations trying to save his family. He was transported to the hospital in stable condition.
The fire marshal says the mother was also transported to Memorial Hermann Hospital in critical condition.
An initial autopsy concluded that the 18-month-old and 6-year-old died as a result of smoke inhalation.
The family did have smoke alarms inside their home, but it's not clear if the alarms went off during the fire. Investigators believe the smoke alarms were powered only by the home's electrical system and "apparently did not function."
"It's entirely possible either these smoke detectors are so old they didn't function. Or the power to that electrical circuit that powers those smoke detectors was interrupted by the fire before it had time to alert the family," Montgomery County fire marshal Jimmy Williams said.
It is not clear how the fire started. The Montgomery County Fire Department is investigating the scene.
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