There's no childhood love that's more pure than that of a boy and his dog. They are our first best friends, and too often our first lessons in death too. Lucas Fuller is only 11, and he's too young to learn that lesson yet.

The hardworking Indiana boy loves his best friend Bear more than anything else in the world, and when Bear got sick, Lucas refused to sit back and watch his friend suffer.

Recently the big dog began struggling to breathe. Coughing and wheezing, Bear just wasn't himself.

"It kind of sounded like kennel cough," Fuller told WGN news. The family also noticed scabs on the dog's skin, and even pus coming out of his eyes. It was clear that Bear was in rough shape.

They took him to the vet who quickly determined that Bear had blastomycosis. A fungal infection that dogs can contract by sniffing dirt. It attacks the lungs before moving on to affect other areas of the body if not treated in time, and it's fatal if left untreated.

There is a cure for Bear, but it's not cheap. Lucas knows that his family didn't have thousands of dollars to spare, so he got to work.

"I really love this dog and I didn't want him to die."

Lucas began canvassing his neighborhood, handing out flyers to advertise his services. He'd do chores and yardwork, for a small price. All of it going towards the treatment to save Bear.

In addition to Lucas's hardwork, his mother set up a GoFund Me page. The reaction from the neighborhood was immediate. The family has already met their $2,000 goal. Someone even paid for the recurring medication Bear would need in advance, anonymously.

Thanks to the neighborhood, and Lucas, Bear is doing better, but he still has months of treatment left ahead of him. At least Bear knows he has a great human friend to help him get through his rough time.

Vets warn that blstomycosis can't be combated with vaccines or shots. It's a fungus found in certain soils and may be more common in areas that are routinely wet or damp (like river beds or lake shores.) Symptoms include skin sores, coughing and puss in eyes or around the nose.

Humans can also contract the infection. Signs include fever, coughing, shortness of breath and muscle aches. It is difficult to contract as a human, but if you have had exposure to infected soil that you may have inhaled, you should consult a doctor.