We're used to seeing celebrity couples on red carpets and out and about, but some of them take their love to a whole new level. Many stars take the stage or hit the recording booth together, writing and/or performing duets that set fans' hearts aflutter. While some musical duos have broken up — Katy Perry and John Mayer and Rihanna and Drake — others' relationships feel as eternal as their music. Though you may recognize pairs like Beyoncé and Jay Z and Miranda Lambert and Blake Shelton, others may surprise you — especially when one half of the couple doesn't sing professionally. The latest was Nicole Kidman and Keith Urban, whose performance of "Amazing Grace" at a children's hospital in Australia will probably make you cry. Keep reading to see that and many more celebrity couple duets!