"Day 4: Draw a pony discovering something unexpected/Draw a pony hiding something.
This one took a bit of inspiration from a story I wrote a while back where Celestia takes Novo on vacation. One scene had them at a marketplace in Ponyville that has a few antique items. When she visited kingdoms before Mount Aris fell under siege, Novo liked looking at all sorts of trinkets and antiques, and sometimes she was gifted some by her late husband. Here she finds an old book, which didn't have much of a description in the story but I interpreted it as a collection of ocean adventures, and Celestia is ecstatic about Novo's joy and curiosity."