Hi Shauna, My kids don't get eye rashes, but I get them. I have them as allergic reastions. As an adult it is a reaction to mascara mostly, but this summer, I had one as a reaction to sunscreen that got too close to my eyes. When I was a child it was a reaction to something in the woods, I still don't know what, but my eyes swelled shut.
Have you changed soaps recently? It could be clothes soap, or shampoo, or baby wash, or lotion.
I would take her in. If it isn't a reaction that you can figure out, it might be something more serious, and you don't want to play games with her vision.
Good luck.