Anybody have an a37 and a57?

I have a nex5 but the camera with lens kit just isn't fast enough to catch my son moving around. I don't want to buy new lenses for it as I'd like to get into dslr/t territory for the long run. I was pretty sold on the a57 but want the 18-135 lens and it was out of my price range so I'm wondering what differences or similarities are there between the a37 and a57? Maybe all I need is an a37 but would like to know what real users think. Thanks!