Dream Theater’s 1999 album Scenes From A Memory is Part 2 of Metropolis Pt.1, a song from their 1992 album Images And Words. They originally put Pt.1 in the title not expecting to ever write a Pt.2, but people kept asking and they did it. 
Most of the similarities are musical, the song and the album being based on different stories and the song having less than completely lucid lyrics, but it’s fun matching up the words.
Brian Wilson wrote “Don’t Worry Baby” as a follow up to the Ronettes’ “Be My Baby”, but Phil Spector wouldn’t let Ronnie record it.
Death Cab For Cutie’s “Company Calls” is followed by “Company Calls Epilogue,” which is a segue and a continuation of the story. I think.
Pearl Jam: Daughter: the shades go down i’s in her head…
Pearl Jam: Rearviewmirror: finally the shades are raised…
Jack and Diane, those two American kids holdin’ onto 16 as long as they can, from John Mellencamp’s 1982 hit Jack and Diane grow up, go to a Ricard Pryor movie and lament how they could have been so wrong in Mellencamp’s late-90s Eden Is Burning.
Sir Rhosis