This photo essay will make any dog lover cry. Anyone who has ever gone through the end of their pet's life knows just how heart-wrenching an experience it is. The story of Duke's last day on earth was chronicled by a photographer.

Duke Roberts, a black Labrador in Houston, was diagnosed a few years ago with osteosarcoma, a cancerous bone tumor, in his leg. Veterinarians removed his front right leg in hopes of stopping the cancer, but the tumor only grew bigger.

According to Duke's owner: “His tumor was growing rapidly and we were out of options. He would rally during the day, but his nights were increasingly uncomfortable as his tumor started to separate his ribs. We struggled with the decision to let Dukey go, but ultimately did everything in our power to protect him from further pain.”

She made an appointment for Monday, July 7 with the vet for euthanization.

Then she called Robyn Arouty, a friend a professional photographer who had shot for Roberts before. She told her about Duke’s last day of life and asked her to come capture it.

Photos show Duke and friends eating hamburgers in the morning. Laying on the floor, eating a hamburger or two, a meal typically forbidden for dogs.

Then they went for a walk... through the "water at the splash park down the street."

The response to the photo essay has been overwhelming. The photos went viral, making their way around the Internet and into the hearts of animal lovers and those who have experienced a similar loss.

Here is a Buzzfeed recap of the photographer's pictures of Duke's last day....