User blog comment:Thailog/Ep. 201 "Happy New Year!" discussion/@comment-175.39.6.37-20120429004653/@comment-91.214.229.2-20120430132411

Wondergirl looks around the same age and height as Batgirl. If Batgirl is indeed Barbara Gordon then they'd both be about a year older than Dick, putting them around 21/22. Superboy biologically is 21 now, even though he's chronologically about 5 1/2, but in the original comics Superboy did not age after turning 16 until later on. If Superboy in YJ doesn't age from 16, it puts him closer in age to Miss Martian, who is about 17 biologically now (54 chronologically iirc). There's all kinds of cloning stuff, alien biology etc. that can skew how you view this. Also remember Wondergirl is Amazonian iirc so there's that factor to put into the mix.