MIDDLEBORO (CBS) – A teenaged girl is credited with saving her mother’s life.

The girl thought her mom was having a medical emergency, but the threat was something else that put both of their lives in danger.

“I didn’t want to lose my mom,” says 16-year-old Annelise Fillion. “I knew I had to do something, so 911 was what I had to do.” Her quick thinking likely saved the life of 43-year-old Cheryl Fillion.

“I’m lucky to have her, and I might not be here today if it wasn’t for her,’” said Cheryl.

WBZ-TV’s Bill Shields reports

It was Saturday morning, when Annelise heard a glass break in the kitchen. She ran downstairs, and found her mother on the floor, barely breathing. She called 911 and when EMT’s and Middleboro firefighters arrived, they smelled smoke, and got them outside. Then, they discovered the home was full of carbon monoxide.

“The 16-year-old in the home did a great job,” says Fire Chief Lance Benjamino.

The chimney was clogged with creosote and pushing the carbon monoxide back into the house.

For some reason, the two carbon monoxide detectors weren’t working possibly because of faulty batteries.

Anneleise’s father, Roger, was away playing hockey and when he got home, and found out what happened, he said this of his daughter: “She’s my hero!”