[playpause]

I don’t think they're logically equivalent at all.

“Are you being a baby?” - Are you temporarily being a bit of a baby, like, at the moment? Could you maybe be a teeny bit braver to get through this current bit of anxiety you're feeling, and then we'll worry about the next bit tomorrow eh?

“Are you a baby?” - Is it possible you have always been a baby? Is it time to grow up, ie, make a real, permanent change to how you think? To start taking responsibility for managing your own emotional responses to the all the inevitable sources of potential anxiety that life will continue to throw at you forever? To break the cycle of weak/passive/burdensome social behaviour once and for all?