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)
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.
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)
Answer: I think I remember that episode - but, more importantly, my mother always told me (and my siblings) to stop jumping/ stomping, running in the kitchen, and opening the oven door when a cake was baking... because these could make the cake fall. I believed my mother... and I, as a child, also caused a few "fallen cakes" because I didn't quite always listen (right away, anyway). I'm sure Alice's fallen cake episode was exaggerated, but cakes really CAN fall from stomps and opening the oven door too soon. Usually, it has something to do with the baking powder and how the air bubbles change during the baking process. Doing something that might cause the oven and cake inside to move/shake can suddenly change the air bubbles inside the cake and cause a collapse. I don't know all factors that have to occur for a cake to fall (collapse in the middle), but I've seen fallen cakes during my adulthood and... well... caused at least a few myself. Regarding Alice's cake falling each time one of the Brady kids stomped upstairs, I'm not sure if a series of falls could occur. IF it is possible, I think there would have to be way too much baking powder in the batter or some other inaccurate combination of ingredients that alter the chemical process during baking.
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