I've always wondered this myself & the only thing I can come up with is that the Brady's were so White Bread & Pure that they didn't need to use spankings. I mean just a simple lecture would have the kids feeling down. It would go something like this:
Peter breaks Mom's favorite vase (or whatever) & then:
Mr & Mrs B would find out & confront the kid with their "Brady Lecture", "Brady Wise Sayings" and most importantly the "Brady Problem Solving" methods. There were groundings as in the case of Greg's having no use of the car for a week or so but usually a stern lecture would do the trick. Or since the kids were so pure their consciences would get to them & they'd repent. I guess there was some Brady Brainwashing going on
So the kids would say "Mom Dad I broke the vase. I'm sorry"
Then the Brady's would say "Fine as long as you learned your lesson & your wise saying of the day like "Caveat Emptor" or something like that.
And the most amazing part was the problems always got solved in 30 minutes or less. You could bake an egg by this format.
Here is a general list of how other shows handled the spanking issue:
Little House on the Prairie: Alluded to but never done on TV. Usually especially in Half Pint's case (Laura) a stern look would have her break down. Usually the kids here just had to do more chores.
Andy Griffith: Depicted several times; not on camera as far as I know + in the "Mr MacBeevey?" ep Andy was set to spank Opie but didn't go through with it cause he trusted his son. It turned out all right at the end.
Cosby Show: None I know of
Family Ties: Same thing
Diff'rent Strokes: There was a show called 'The Spanking" where Willis of all people ended up spanking Arnold instead of Mr D. Of course Willis feels bad about it & learns a lesson about discipline in that typical "guilt trip" way. Arnold's butt was sore though.
I guess in general much like the Brady Toilet thing that was universal standard at the time (until Archie Bunker flushing became a gag) spanking on the air was deemed bad or not PC I reckon. However in general when it came to shows w/TV families the 'Guilt Trip Lecture/I'm Sorry Dad" method was used as were Groundings or Chores or my personal favorite: Go to Your Room.
Mostly though the kids were so well behaved & stuff it didn't matter. For especially in the Brady's case they were Mormans or something like that.
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