Lex was the former dog of Corporal Dustin Lee of Stonewall.
Lee was killed, and Lex injured in Iraq in 2007, and Lee's family adopted Lex, but now, that link to their son is gone.
Rachel Lee, Dustin's mother and Lex's adopted owner, says she knew this day would come eventually, but knowing it didn't make it any easier for the family that had grown so close to Lex.
"Besides the obvious of being able to touch something Dustin touched, it goes beyond," says Lee.
Lex, along with Lee, helped deliver Dustin's message across the country, providing unique therapy to wounded soldiers, and giving children a chance to hear Dustin's story.
With Lex gone, his family is making sure he will not be forgotten. Right now Lee says that military working dogs are officially classified as equipment, but her experience with Lex has led her to fight for a change to that title.
"That was one of our goals, to change the outlook of the way people look at military working dogs."
Another goal for Lee, fighting for federal support for families who adopt animals who served in the military.
Lee started a fund called Angels for Lex. That fund helped her pay for treatment for the dog that so bravely looked after her son.
With Lex gone, Lee says her work is not done. If you would like more information on military working dogs, and to keep up with Lee's work, you can search "Angels for Lex" on facebook.