Saint George, Canada - This pit bull is a true hero! In a flash this dog got help when he saw his human brother on the ground outside.

About a year and a half ago, Candia Merchant rescued Charlie the dog from an abusive household. Now Charlie has paid his family back richly, according to The Dodo.

When one of the family's three children, Donny (14), went into the backyard shed one day in April, Charlie watched carefully.

Donny was looking for his fishing rod when he encountered a hornet. For most people, a sting would be a bit painful but nothing to worry about.

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However, Charlie could see from the window that something was wrong. When Donny collapsed in front of the shed, his four-legged brother went nuts and began barking.

Candia explained, "Charlie started running back and forth across the floor in a panic, barking at the window, shaking, and we could tell there was a reason, as Charlie doesn't bark that much."

"Charlie knew Donny was in trouble," the Canadian explained.

Looking out the window that day, the mother saw her son lying on the ground. Hastily, she ran to him and immediately realized that Donny had an allergic reaction to the hornet's sting.

Until that moment, the family had no idea that the teenager was allergic to hornet stings, but his mother knew exactly what to do from her own experience.

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Merchant, who has the same allergy, ran into the house to get her medication, and after her son was taken care of, she drove him to the hospital.

"After my son was stung, Charlie refused to leave his side for almost two weeks," Merchant gushed, adding, "I know if it wasn't for Charlie, Donny would be dead."

For this dog, the title of "good boy" is probably an understatement!