Amongst geese too unruly to upset a person (3,8,4)

I believe the answer is:

get someones goat

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'upset a person' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'amongst geese too unruly' is the wordplay.
'unruly' indicates anagramming the letters.
'amongst'+'geese'+'too'='amongstgeesetoo'
'amongstgeesetoo' anagrammed gives 'GET SOMEONES GOAT'.

'to' is the link.

Can you help me to learn more?

(Other definitions for get someones goat that I've seen before include "Bug one" , "Attack a person's kid" , "make them angry?" .)

I've seen this clue in The Times.

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