Was it written and filmed before A Very Brady Christmas aired (and got high ratings)? What is the relation of the two? Was the episode allowed because they didn't have high expectations for A Very Brady Christmas? Or was it quickly created because of the success of A Very Brady Christmas?


December 18, 1988 - A Very Brady Christmas airs on CBS.

February 5, 1989 - "A Very Brady Episode" (https://www.drunkmonkeys.us/2017-posts/2021/3/8/one-perfect-episode-day-by-day-a-very-brady-episode-rc-hopgood) of Day by Day airs on NBC.

May 19, 1989 - Maureen McCormick gives birth to her daughter.

throughout 1989 - CBS/Sherwood Schwartz start developing The Bradys after the success of A Very Brady Christmas.

December 1989 - “work began on” The Bradys.

February 9, 1990 - The Bradys premieres on CBS (and lasted just 6 episodes).

February 17, 1995 - The Brady Bunch Movie is released (Greg is played by Christopher Daniel Barnes who played Ross Harper / Chuck Brady in Day by Day).

August 23, 1996 - A Very Brady Sequel is released (Greg is again played by Christopher Daniel Barnes).

I would guess A Very Brady Christmas was filmed first and was probably in the works in the summer of 1988. They had to develop a script and bring everyone together. A sitcom is already in motion and a flashback Brady episode that lasted 17 minutes in the Brady house would take much shorter time to film and put together. It also aired a few months after the Brady Christmas. Maybe the success of the Brady Christmas made Day by Day throw together a Brady script. I can see that happening.
I remember the joy to have the Bradys back on TV just months apart.