So, the mesh warp effect in After Effects produced results that were, um... interesting. Padme's arm gets all noodly to begin with, and then it looks like one of the babies has a major Jedi kick.

I'm going with a video composite of a "belly ball" which won't change shape instead. Lesson learned.

The video available here contrasts the warped video to the composite test I did with the ball pretty much matching Padme's movement. It's really brief, so you may want to loop your playback or manually rewind.

If anyone has any tips on the best way to do the composite, I'm all ears (particularly about the simplest and most effective approach to painting the ball to look like Padme's gown).