Just the girl to mother one? (3)

I believe the answer is:

mai

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'just the girl' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'mother one?' is the wordplay.
'mother' becomes 'ma' (Ma is another word for mother or mum).
'one?' becomes 'i' (Roman numeral).
'ma'+'i'='MAI'

'to' is the link.

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I've seen this clue in the Evening Standard.

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