It was a simple gesture, but a huge milestone for Randy Travis. They've been coming slowly, but steadily for the Country Music Hall of Famer. Wife Mary recently shared the latest.

During an interview with CNN, Mary recalled driving home to Tennessee one day. "We were coming out of Memphis and overhead was a sign, 'Nashville' and he was over in the passenger seat and went, 'woo hoo' and he pointed up and he said, 'Nashville,'" she says. "I just sat over there in the driver's seat and cried because I knew then that he read that sign, and he recognized the word, and then he said it. That's a huge thing. Huge for us."

Additionally, Travis is able to listen to his own music again — something he couldn't bear to do early on. One song in particular has become his anthem, a song he's not famous for but has performed many times. "Amazing Grace" describes their journey, Mary says. Travis sang the song at his induction into the Country Music Hall of Fame last October, and again during a concert to recognize his music earlier this year.

Watch Randy Travis Sing "Amazing Grace"

"Music is his soul," Mary Travis says, adding that they don't worry about a second stroke. This summer will mark four years since a virus led to heart troubles and eventually a stroke. She's recounted many times how doctors urged her to pull the plug, and the couple has been candid about his recovery and rehabilitation since then.

See Randy Travis Through the Years

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