Grandmother's girl (3)

I believe the answer is:

nan

I believe this clue is a double definition.

'grandmother's' is the first definition.
(nan can informally mean a grandmother)

'girl' is the second definition.
(Nan can be short for Nancy or Anne)

(Other definitions for nan that I've seen before include "Indian bread - older relative" , "Grandmother (colloq.)" , "Elderly relative" , "Indian bread; grandma" , "Relation" .)

I've seen this clue in the Evening Standard.

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