Which of these is a by-product or incidental result of a larger project?

I think the record holder for the amount of spinoffs from an American tv show, has got to be Happy Days. They had 3. Lavern and Shirley, Joanie loves Chachi and Mork and Mindy. There was also a brief spinoff from the spinoff Lavern and Shirley, when Squigy and Lenny had a few episodes on their own.

I guessed right but sequel is dangerously close to the correct answer. Thumbs down.