The Traveling Kind by Emmylou Harris and Rodney Crowell
Bless you, Emmylou.
“We embrace our age,” says Mr. Crowell. “And we’re old friends. ‘La Danse de la Joie’ is the narrative of that. A couple of old people dancing—OK, we may be broken down but we got this, come on!”
http://www.wsj.com/articles/more-duets-from-emmylou-harris-and-rodney-crowell-1431448433