Continuity mistake: The shadow (supposedly of the window frame) on the headboard of Jan's bed changes from one shot to the next. (00:24:35)
Kitty Karry-All is Missing - S1-E7
Continuity mistake: As Bobby empties his pockets in search of his kazoo, he piles the contents on a nearby table. In a long shot, several of the toys (most noticeably a green plastic paddle) disappear, only to reappear when Cindy is leaving the room. (00:18:10)
Continuity mistake: The tents are small from the outside, but much larger when seen from the inside. (00:18:25)
Is There a Doctor in the House? - S1-E13
Continuity mistake: When Carol and Mike are bringing stacked lunch trays upstairs to the kids, the milk glasses on the middle and bottom trays that Carol's holding switch to the opposite sides twice, in the wideshots and closeup. Then when Carol picks up the girls' stacked trays, the glass of OJ is on the bottom tray (after Peter's reaction to broccoli, it looks as if the OJ glass is gone), then as Carol walks into their room the OJ is now on the middle tray.
Continuity mistake: When Alice enters the kitchen you can see the ironing board from the doorway. When she is giving Tiger a bath the Ironing board has moved to the wall that can not be seen from the doorway. (00:01:30 - 00:04:05)
Continuity mistake: When Marcia takes her last turn placing a card at the top of the tall house of cards, in the shots facing her she's stressed about accidentally collapsing the cards so she holds back her charm bracelet with her left hand, but in the first shot facing the three boys Marcia's left arm is down at her side and the charm bracelet is dangling at her wrist, right beside the cards. (00:21:00)
Continuity mistake: When the kids are building the card castle to see who would get to choose what they get with the stamps, Jan is putting a card on, in one shot her hair is up in a ponytail then in the other shot her hair is down. This happens back and forth when the shots change.
Continuity mistake: The amount of cookies in the cookie jar Bobby is holding increases from one shot to the next. (00:10:20)
Continuity mistake: In a close-up of Mike's hands as he undoes his seat belt, he isn't wearing his wedding ring but he is in subsequent shots. (00:04:15)
Continuity mistake: When Mike walks into the kitchen asking Alice if he can give her a hand, Alice removes two pots from the stovetop leaving the left side clear, but in the shots from the dining room when Alice trips, there are two large pots on the left side of the stovetop, near the edge of the counter. (00:01:20)
Continuity mistake: The amount and position of the soapsuds on Jan's shirt changes from shot to shot. (00:09:20)
Continuity mistake: The bottles of pop on the kitchen table keep changing position from shot to shot. (00:22:55)
Lost Locket, Found Locket - S1-E25
Continuity mistake: Jan puts her bathrobe on, flipping all of her hair behind her back. But in the next shot, some of her hair is over her left shoulder. (00:20:30)
Lost Locket, Found Locket - S1-E25
Continuity mistake: When they are getting ready for the reenactment of the night when Jan lost her locket, Greg is about to eat an apple when the boys walk into their room. When Greg sits down, his apple is mostly finished.
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.