Cyrus and Fallon had previously collaborated on another song made famous by Parton. In a surprise busking appearance in the New York City subway, they performed “Jolene,” with Cyrus taking the lead vocally. After revealing their identities, the pair continued with Cyrus’s “Party in the U.S.A.” and involved the gathered crowd in the performance. Video of that subway session drew 52 million viewers on YouTube.

Parton’s role as Cyrus’s godmother can be traced to 1992. At the time, Miley’s father, Billy Ray Cyrus, toured with Parton while promoting “Achy Breaky Heart,” his breakthrough hit. The two became friends during that period. When Parton later discussed their connection on The Howard Stern Show, she noted their regional ties: Billy Ray was a Kentucky native, while she came from Tennessee.

According to Parton’s account, Billy Ray told her that a daughter was on the way and asked her to serve as the child’s godmother. She regarded the invitation as an honor and agreed. In the years afterward, the relationship shifted toward Parton and Miley, and the two maintained a very close bond.