Will They?
Because of the show’s marginal ratings (it only reached #34 in the Nielsen Ratings), the show was never actually renewed for an entire season until its last season. During the first four seasons, it was only ever renewed for 13 episodes at a time. Many cast members admitted that when filming 13 episodes wrapped up, everyone felt apprehension while waiting to see if ABC would even renew the program.
My Idea
So the producers of Yours, Mine and Ours actually threatened to sue Sherwood Schwartz, as they accused him of taking their idea and plot summary for the show. Once Sherwood showed them his notes and outlines of the show, which was written a year or so before the movie was written, they backed off.