Eight-year-old Annberly loves looking out for her little brother Joseph.

She's a very protective big sister -- always there to help. Back when Annberly was only 7, that instinct, along with some basic first aid knowledge, may have saved Joseph's life.

Jessyei Sills is Annberly and Joseph's mom, and explains that one day she was in the kitchen and heard Annberly screaming and crying. She thought that maybe Joseph was just pinching her and biting her, but she was wrong.

"I get in there and she's smacking him on the back, with him over her legs and something comes out of his mouth and I'm like, 'What's going on?' And she said, 'He's choking mommy. He's choking,'" Jessyei explained.

Annberly had a collection of eraser tops, and Joseph got one lodged in his throat.

She knew what to do when someone was choking because her parents taught her how to do back blows from a very young age with a baby doll.

Now Joseph is just fine, thanks to a big sister who knew what to do in an emergency.

"She always reminds him, 'If I wouldn't have saved your life, you wouldn't be here right now. So be nice. Stop biting me,'" Jessyei said.

It's a story that's sure to come in handy when they're teenagers.

The American Red Cross offers CPR classes, click here to find one near you.

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