Revealing mistake: When Peter is on the trampoline, instead of saying "Peter," Carol says, "Go get 'em, Chris!" and a few minutes later the same thing happens after Cindy has a turn alone, you can hear Greg say "Why don't you give it a try, Eve?" (00:18:10 - 00:19:50)
Confessions, Confessions - S2-E12
Revealing mistake: At the start of dinner, in the wide shots we can see the table and chairs directly on the carpet. When Carol notices the leaky vase and calls for Alice, in the wide shot as Alice approaches the table, now there's plastic sheeting spread across the carpet under the table, as well some visible tubing under the table, presumably for the water stunt. (00:05:45 - 00:08:15)
Lights Out - S2-E20
Revealing mistake: When Peter is on stage at his school for the talent show, Cindy gets into the disappearing lady booth and Peter closes the curtain. He says the magic words, yanks open the curtain and Cindy has disappeared. Look at the top left side of the booth and you can see where the stage curtain is piled up on top of the booth. There is just enough room for Susan Olsen to get out of the booth and then get back in.
Alice's September Song - S2-E23
Revealing mistake: One of the times that Sam comes over to visit Mr. Brady, he comes in through the back sliding "glass" door. There is no glass in the door. You can tell this because when Sam closes the door, to do so, he puts his hand through the areas where glass would be.
Answer: Much trivia has been written about "The Brady Bunch, " including the various interrelationships and dynamics among the members of the cast. For example, much has been written about why Robert Reed's Mike Brady did not appear in a couple of episodes, including the series finale, due to rancorous creative and artistic differences with series creator, Sherwood Schwartz. However, in contrast, I have never run across any reasons given why a particular child did not appear in specific episodes - only that the episodes were missed. This suggests the causes were likely unexceptional, such as illness, injuries, vacations, or real-life family obligations.
Michael Albert
Although those options ARE possible reasons, it just seems a bit ironic that this happened all in Season 2 ONLY and within a short amount of nearly consecutive episodes. Never happened during the other 5 years of the show at all.