Shane Godfrey spent five weeks in the hospital battling the flu, and he lost 50 lb. He looked totally different by the time he was able to go home, and that's why his dog Willie didn't recognize him. Not until Willie got close enough to smell Shane, and realized that his person was finally home! You can see the light bulb moment, and it's enough to make even the most cold-hearted person have some serious feels.
h/t Mandatory