Blue bonnet in Charlotte's infancy? Far from it (9)

I believe the answer is:

adulthood

I'm a little stuck... Click here to teach me more about this clue!

'charlotte's infancy? far from it' is the definition.
I can't judge whether this defines the answer.

'blue bonnet' is the wordplay.
'blue' becomes 'adult' (blue can mean pornographic or adult).
'bonnet' becomes 'hood' (synonyms).
'adult'+'hood'='ADULTHOOD'

'in' is the link.

Can you help me to learn more?

(Other definitions for adulthood that I've seen before include "Full maturity" , "Supposedly mature years" , "Time for a majority" , "Grown state" .)

I've seen this clue in The Independent.

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