What baby might need is courage (6)

I believe the answer is:

bottle

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'is courage' is the definition.
(bottle can mean courage)

I cannot understand how the rest of the clue works.

(Other definitions for bottle that I've seen before include "Vessel for liquids" , "cool" , "(Drink) container" , "The spirit" , "Glass or plastic container" .)

I've seen this clue in The Guardian.

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