Trivia: Among the girls at the slumber party are Florence Henderson's daughter Barbara ("Ruthie") and Robert Reed's daughter Carolyn ("Karen"). They interact briefly; during the game of Truth Or Dare, Ruthie is dared to go check on the boys and asks Karen to go with her. In addition, Hope Sherwood ("Jenny") is the daughter of executive producer Sherwood Schwartz.
Trivia: In Season 2, out of the five episodes with one of the kids not appearing in the entire episode, three episodes used the name of the missing kid in the dialog most likely to make their absence from the episode more unnoticed. (Marcia/Peter/Bobby in these cases - each one's name mentioned at least once even though they never appeared). The episodes were ("What Goes Up...", "The Tattletale" and "Coming-Out Party"). Also the 4th episode of season 2 - "A Fistful of Reasons" contained Jan being mentioned yet she did not appear in the entire episode.
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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