Crossword Genius

Younger son acted wrongly (5)

Ross

I believe the answer is:

cadet

'younger son' is the definition.
(archaic term for a younger child)

'acted wrongly' is the wordplay.
'wrongly' indicates an anagram.
'acted' with letters rearranged gives 'CADET'.

(Other definitions for cadet that I've seen before include "Trainee cop" , "Police or armed forces trainee" , "young soldier" , "Apprentice officer" , "Officer in training" .)

I've seen this clue in The Sun.
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