Amy faked her continued illness, so Sheldon would take care of her. He decides to punish her by spanking her. She likes it!
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Amy gets sick and Sheldon takes care of her and that means putting Vaporub on her chest. She likes it!
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Will Sheldon be able to play nursemaid when Amy takes ill on The Big Bang Theory. "The Fish Guts Displacement" is the tenth episode of the show's sixth season.
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The Big Bang Theory Season 6 Episode 10 Quotes

Death by chicken. That's a pretty fowl way to go.

Howard

Amy: Sheldon, aren't you gonna take care of me?
Sheldon: Me? No. I'm not that kind of doctor.