The singer told People that she sees more of his "softer" side on the show.
"It's hard to explain," she said. "He's so protective of his [Voice team]. He has this side to him that I didn't know about."
Lambert also joked that Shelton is a "ham" on television but added: "I see this side of him that's softer, almost fatherly or big brotherly."
Lambert and Shelton married last May after being engaged for a year.
The Voice airs Mondays and Tuesdays on NBC.
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