A Siberian Husky helped his owner detect her cancer without any formal training.

According to the Milwaukee Journal Sentinel, the then-9-month-old puppy, Sierra, came to live with Stephanie Herfel when one day the dog started acting in a strange way.

The Husky reportedly sniffed Herfel’s abdomen so closely many times before hiding in the closet out of fear.

Herfel soon found out that she had ovarian cancer.

Dogs have as many as 300 million olfactory receptors in their noses, making their sense of smell 10,000 to 100,000 times better than humans.