Fact this season Fluttershy is getting the most character development then the rest of main 6. Here why I thinks that her why fact Fluttershy seem to agree with Starlight equality in first time she walk in the town. Fact she told rainbow dash the cold hard truth that she will have to remain pet less. Another fact that we would end meeting her brother in October tell me one things something going to happen to her this season.

4717947 Well, I don't think it will happen in season 5, but it was leaked a long time ago that Fluttershy will ascend (Become an Alicorn Princess) in some season.

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I don't think it counts as development when none of it sticks...