My twin girls, eg, excited about king character in Potter book (3,5-6)

I believe the answer is:

mrs tiggy-winkle

'character in potter book' is the definition.
(Beatrix Potter character)

'my twin girls eg excited about king' is the wordplay.
'excited' is an anagram indicator.
'about' is an insertion indicator.
'king' becomes 'k' (abbreviation for king in chess).
'my'+'twin'+'girls'+'eg'='mytwingirlseg'
'mytwingirlseg' with letters rearranged gives 'mrstiggywinle'.
'mrstiggywinle' placed around 'k' is 'MRS TIGGY-WINKLE'.

I've seen this clue in The Times.

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