Child of the captain mentioned (3)

I believe the answer is:

kid

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'child' is the definition.
(I know that child can be written as kid)

I don't understand the remainder of the clue.

(Other definitions for kid that I've seen before include "Goat - boy" , "Young animal or child" , "In slang, young child or goat" , "Schoolboy" , "To fool; young animal" .)

I've seen this clue in the Evening Standard.

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