Any Brady fans out there?. From 1981, here comes the story :
"The Brady Girls Get Married" was a TV movie reuniting the bunch from the 1969-1974 TV show, where Jan and Marcia Brady were both getting married at the same time. They had a double wedding.
Now, the network cut the movie up into 3 episodes instead(but later airings on TV were as the full length movie), and turned it into a brand new series, "The Brady Brides", which went on to air 7 more individual episodes afterwards(in a more sitcom style, complete with the first live audience for a Brady show), before being canceled.
Opening credits: