An alert therapy dog is being hailed as a hero, after warning attendees at her own birthday party about a backyard fire.

Attendees at the Calgary house party were alerted to look outside after the dog, named Twillow, repeatedly approached the home's backyard door.

"All I heard was ‘The house is on fire, call 911!'" Straja King told CTV News, describing what happened next.

A fire, sparked by linseed oil-soaked rags, warped plastic siding and destroyed a section of the home's fence.

King credits Twillow for keeping everyone safe.

"If it weren't for Twillow, we wouldn't be having this conversation because it was that close to the house," King said.

Calgary firefighter Carol Henke knows how valuable a pet can be: a dog warned her of a fire in the middle of the night before she became a firewoman. But she cautions that having a pet on hand isn't a guarantee of safety.

"Pets can alert us to danger, but in no way should we be relying on that," she said. "Having a working smoke alarm is key to the entire family's safety."

With files from CTV Calgary's Bill Macfarlane