I know her. She isn't 12, she's 22. I know kids are dressing sluttier these days trying to look older and all, but seriously, she has a young face and the body of a mature adult. She has fully-developed breasts and she isn't in any 'ugly-duckling' phase where her body isn't proportionate because it's growing quickly. Also, what 12 year old has room that looks like that? Possible? Sure. Likely? Nope.
Use your brain.