Dogs are often treasured members of our families. Serving as protectors, playmates, friends and loyal companions (not to mention a living Roomba in the kitchen), our furry family members have unique and special gifts. It’s no wonder canines hold high esteem within the military. With the ability to detect traces of illegal substances, explosives and other humans, they’ve proven to be an invaluable asset to forces around the world. While we honor the sacrifices of veterans on Nov. 11 each year, military working dogs have their own special day on March 13—K9 Veterans Day.

On March 13, 1942, the U.S. Army officially began its War Dog Program (also known as the K9 Corps) in conjunction with the Dogs for Defense private organization. However, there is a long history of unofficial canine service dating all the way back to the 7th century BC when they were used to deliver messages and as sentries. Today, potential candidates are put through a rigorous training and screening regimen before they are selected to serve in the corps. Once they’ve been chosen, they are sent to units around the world.

One of the most famous canine war heroes was Sgt. Stubby, a stray Boston-terrier mix who was eventually adopted by Cpl. Robert Conroy in 1917. When Conroy’s unit left for France, he managed to secretly stow Stubby onboard the ship. Upon discovery, the commanding officer allowed Stubby to remain with the unit. For 18 months, Stubby served in four major offenses and 17 battles. He was injured twice, once during a gas attack and the other from shrapnel after a grenade exploded nearby. He was bestowed the rank of sergeant for his service. After the war, Conroy was able to bring him home where he lived the rest of his days in comfort and as a celebrity, including a stint as the official mascot for Georgetown University.

While military working dogs are often overlooked as veterans, it’s important to remember these loyal service members also sacrifice when defending our freedoms. On March 13, take a moment and honor these amazing animals.