How do I change the animation of a sprite used as a face object?

How do I specify to change the animation of the specific instance of the sprite that's on the specific instance of the 3d object?

ie. I've got an enemy that's a 3d box, and the bottom face is the 2d sprite I want to represent the enemy. I need to change the animation of that specific instance, but everything I've tried (for each, etc) sets the animation for every instance of the 2d sprite. How do I address the specific instance that's on the specific instance of the 3d box, so that it can change the animation independently?

Nevermind. Got it. Create an instance from an event sheet at the start of the layout, make it invisible, set it as a child of the 3d object, then make that instance, while we're still talking about it (from it having just been created) the bottom face of the object. Pick its own child then change the animations. Works a charm. All good.