Attitude.

I didn't realize how closely Rosie and Cocoa Puff resembled each other until I took this photo.

And here is how Websters defines attitude...

Attitude-(noun)  position or posture of the body appropriate to or expressive of an action, emotion, etc.

So the question remains...

How on earth is it that girl and pony could have the exact same countenance at the exact same moment in time?

It seems that an aged pony and a four year girl old can eerily sync when it comes to important things like feisty girl attitude.
Who knew?