? Nothing's missed with tenatwist ? And finally tonight, we know 23,000 American troops will be leaving Afghanistan by the end of this year, hoping to bring some friends with them. Friends who also... See More
? Nothing's missed with tenatwist ? And finally tonight, we know 23,000 American troops will be leaving Afghanistan by the end of this year, hoping to bring some friends with them. Friends who also showed a lot of courage in combat. ABC's Jonathan Karl tells us about the four-legged veterans who deserve home and family, too. Reporter: A service member's best friend. And nowhere is the bond tighter than when they have been in battle together. Sergeant Jason boss and CICI the chocolate lab spent a year together in Iraq. This is my best friend. This is my partner. Reporter: Conducting nearly 100 missions, seeking out enemy explosives and weapons, keeping each other company. This is who I talk to every single day, so, you know, that bond grew pretty quickly. Reporter: When sergeant boss left the army, CICI stayed behind. But with some help from the American humane society and mission canine rescue, they were reunited 18 months later. There have long been dogs of war. This photo is from world war ii. Some 3,000 dogs have served in the U.S. Military since 9/11. When they retire, they are put up for general adoption. But now, there is a movement to reunite them with their battle mates. Not just for the dog's sake. We'll never label them as pets. We call them our partners. Reporter: James Harrington was awarded the bronze star after he and his dog helped rescue wounded soldiers in Afghanistan. Back home, Harrington suffered from PTSD, but after 2 1/2 years, riki is by his side, helping him again. She saved me and other soldiers, and now she's going to continue to save me emotionally as we go along. Reporter: Their battle mates. Best friends. And more. Jonathan Karl, ABC news, Washington.
This transcript has been automatically generated and may not be 100% accurate.