I am not sure where to post this question:

This is from a TV script:

"Now Annie, all of 12, has always been precocious, but she’s 
got a good head on her shoulders and I like it when she uses it..."

I know that "all of 12" refers to her age but why "all of"?

Thanks!
Hi,
It's an idiomatic expression meaning 'she is only 12'. You might consider it an ironic statement.

Clive
Clive
i d like to ask u stg more.

Do that (all of 12) statement have "despite" meaning?
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Hi,
"Now Annie, all of 12, has always been precocious, but she’s 
got a good head on her shoulders and I like it when she uses it..."

Do that (all of 12) statement have "despite" meaning?

Yes, broadly speaking.

"Now Annie, despite being only 12, has always been precocious, but she’s 
got a good head on her shoulders and I like it when she uses it..."

Clive