Here's how the whole thing went down. We're told the unlikely friends met last year at the White House, where the 15-year-old dared Baldwin to get Hannah Montana's initials and in return she would let him appear on her Disney TV show since his daughters are huge fans of the series.
Fast forward to yesterday in Nashville, where sources tell us Miley's little sister, Brandi, heard on the radio that the 42-year-old outspoken Christian was also in town to promote his new book. So Miley, her mom, Brandi and Miley's boyfriend Justin Gaston decided to surprise Baldwin at a book signing. When they arrived, we're told Stephen showed off his "HM" tat and asked if he could cameo on her show, at which point Miley (reluctantly?) agreed.
It's Miley Cyrus' world and Stephen's just livin' in it.