Samantha's Magic Sitter - S8-E15
Trivia: This is the same as Season 1 Episode 27 There's No Witch Like an Old Witch with the amazing Marion Lorne as Aunt Clara, the goof up witch babysitter-with much of the same dialogue. The plot is essentially the same.
Answer: Larry had been telling Darrin what it means psychologically that Samantha gave the coat away. Larry said giving it away meant she's happy being married but if she liked the coat it means she desires to be single and carefree. So when Darrin sees the coat, he immediately thinks Samantha doesn't want to be married and the fact that she twitched it means (in his mind) she wants to be a single, carefree witch again.
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