I think the Pappy O'Daniel reference is to a scene in the Coen Brothers' movie "O Brother Where Art Thou" in which Pappy (a character based on a real life Texas politician and radio host of that name, played by Charles Durning) introduces a group on his show singing Sunshine.
Every year, hundreds of references appear in mass and social media making unexplained and even unidentified references to Coen Brothers' movies. Sometimes I recognize them, often not.