Director's cut: A Giant Adventure to Equestria, chapter 17

The decision of whether to keep Eric Reed 4 inches tall or return him to a normal, I went back and forth on. I ended up just doing both somewhat by having the size-fixing effect of the counterspell be temporary. This way, the door would be open for me to later write shorter stories or one-shots with him at his normal height, as well as some when he's 4 inches or even smaller.

An idea I ended up scratching was that, in the final chapter, Eric was going to write Twilight, Pinkie Pie, Rarity, Rainbow Dash, Fluttershy, Applejack, Spike, and Starlight an individual letter on something he learned from them from watching the show. This idea was before Starlight's role in the story became so big, so once it did, I thought him having a tight bond with her as well as Twilight was enough. If I left her role as it was going to more-or-less be, her bond with Eric would've been about the same as his bond still is with the rest of the mane 6: a friendly bond, but not a brother-sister level bond as it is now, and she wouldn't had been as protective of him as she is now. Sure, she'd still want to protect him, as she would any of her friends, but the urge wasn't had been AS strong.

I also wanted his bond with Twilight and Starlight to be unique compared to the rest of the mane 6, which is why Eric doesn't think of the rest of the mane 6 as his big sisters, but instead as really good friends, but he does think of Spike as a younger brother. This meant I needed to scratch the letter idea.

Not to mention, there's the irony of how Twilight and Starlight, the two ponies that tried to crush Eric to death when they first saw him, became the ones he's the closest to.