Girl, nine, starts wearing ponytail twisted in an affecting manner (10)

I believe the answer is:

poignantly

'in an affecting manner' is the definition.

'girl nine starts wearing ponytail twisted' is the wordplay.
'starts' says to take the initial letters.
'wearing' is an insertion indicator.
'twisted' indicates an anagram.
The initial letters of 'girl nine' is 'gn'.
'ponytail' anagrammed gives 'poiantly'.
'gn' going inside 'poiantly' is 'POIGNANTLY'.

(Another definition for poignantly that I've seen is " In a way such as to evoke sadness or regret".)

I've seen this clue in The Guardian.

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