Pretty sure she is 18 now. There was one poster a while back (name escapes me) salivating at the possibility of her becoming legal.
Here is the fucked up thing to consider. Women (she is a woman now) who don't look "adult" tend to be excessively promiscuous to make up for what they are lacking in feminine sexuality traits.
TLDR: Greta has probably swallowed more cock than your average soggy getbigger.