Gilbert's in trouble. Getting the pox? (10)

I believe the answer is:

blistering

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'getting the pox?' is the definition.
I can't tell whether this defines the answer.

'gilbert's in trouble' is the wordplay.
'trouble' indicates anagramming the letters.
'gilberts'+'in'='gilbertsin'
'gilbertsin' anagrammed gives 'BLISTERING'.

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I've seen this clue in the Sydney Morning Herald.

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