Transcript for Army veteran reunites with dog he worked with in Afghanistan

Finally tonight here, America strong. The soldier and his partner on the battlefield, reunited. The army specialist and his dog. Army specialist Joe Steinbeck served in after began stay with Tess, trained to detect bombs. They were partners. For a year and a half, Tess protected Joe and his troops from hidden explosives. He was separated from Tess when he returned home in 2013, treated for PTSD, he has been trying to adopt Tess ever since. The last time I saw her was right when we touched down back in America from our deployment and got five minutes to say good-bye to her. Reporter: And finally, over the weekend -- There she is. Reporter: After nearly six years, this was the moment. They were reunited in Connecticut. Tess is now retired from service. They are together again at Joe's home in Indiana. Tess and that bond returning in an instant. It feels like it's been a lifetime, but it also feels like it was just yesterday that I said good-bye to her. Just having her around, I mean, I can't tell you, I mean, the past two nights, I've ever slept better. Reporter: Tonight, Joe tells us his goal now is to reunite other dogs with their partners from the frontlines. Tess is home. I'm David Muir. I'll see you tomorrow night from Washington. Good night. Good night. Driving in New York City isn't easy.

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