You are already booped.

I wonder how long it takes to properly grow into Tia-dom. Cady is already taller than the average mare and flashbacks show she's not super-old (she was visibly smaller when Twi was a kid.) Maybe it doesn't take centuries. I don't think we'll ever have Twilight walking around in every episode ever as a goddess with a galaxy mane, but it'd be neat if she were a little taller every season, to have an inch or two on the others by the end.Of course, it probably wasn't intentional. Maybe in this shot they were just a little closer to the same height than usual, wouldn't be the first time someone gained or lost an inch because of an animation… thing.As for any normal growing left… it seems pretty clear that none of the Mane Six are less than adult. I don't know too many kids who live alone and run businesses and such.