PRIMARY school student Isabelle Grigoriants was fast asleep when she was woken by her grandmother's irregular breathing.

All alone at her grandmother's house in Carnegie, the seven-year-old tried to wake her that night in July, but she would not rouse.

Life saver: Isabelle Grigoriants tells how her speedy action helped save her grandmother's life. Credit:Justin McManus

Remembering her school training, the cool-headed Isabelle called triple-O for help.

"I was thinking 'Oh, my God, what should I do, should I call triple-O or call mum'," Isabelle said yesterday after receiving a bravery award for her actions.