@Casi, I did the same thing! I couldn't find anything similar so maybe you are right and she did take the listings down.
As an artist, I always worry about my ideas being an original. So when I finish a drawing and I try to figure out tags and such, I often end up searching out my own item. I am always astonished at just how many people do think alike. It is nuts but of course we are all human beings that are bound to think alike at some point.
I really hope she wasn't copying you because that is sad. There is an endless amount of ideas out there! Endless, so I can't understand why you would skip the fun of finding your own way into an idea.
Like sprywhimsy mentioned, owls are rampant. They are adorable, mysterious and beautiful. Tons of people LOVE owls. I am one of the many. I didn't look up anyone else's owl drawing, painting or artwork when I was drawing my own. The fun part was creating the owl in my own creative flow. I would just think that would just suck the fun out of creating something. Copiers are only robbing themselves of the reward of creating a unique design.
So if she did, hopefully you letting her know you saw it and don't apprecite it too kindly will keep her from continuing and from doing it to someone else. If she gets back to you and says she wasn't copying there is a possibility it was unintentional.