I have decided to start the process of switching Aidan's room and the guest room. The room Aidan is in now is rather small and will work just fine as the guest room. The room he is moving into is large, which is great, but it is strange. It was originally a game room. The previous owners decided to make it into a bedroom, and they did not do a very good job. You can see where the drywall meets on the outside of the room, there is an odd ridge along the upper left side inside the room where that drywall was added, the crown molding stops in mid-wall, and they decided to leave the hole in the wall that was meant as a "window" to look down on the entryway. They put a fish tank in this hole in the wall. Here is the picture from when they had the house listed.

They asked us if we wanted to keep the fish tank, and I promptly said no. It was old, nasty, and I could just imagine what my kids would do to those poor fish.
So, we have had a hole in the wall in our guest room. I hung curtains inside so that our guests could have some privacy.
I considered many different options on how to deal with this problem cheaply before moving Aidan. Ideally we would have the drywall guy come, do away with it, and fix the other issues. Since that's beyond our budget right now, I finally landed on this.
I had the mirror cut that was originally in the kids' bathroom and attached it behind the hole. Liquid nails is my new favorite product. I would like to put the little wood pieces on the mirror to imitate a cute french window eventually.

I then put in insulation behind the mirror because I have had some complaints of noise traveling into the room easily. Next I took a piece of plywood, sprayed texture on it, and nailed it on top of the insulation. After some caulking and painting, there is now an art niche inside the bedroom. The paint is actually still wet. I'm too impatient to let it dry before putting in frames.
I also bought some wood to make three bookshelves. Before I move Aidan it will become a bookshelf area with maybe a little desk or table below. For now though, I no longer have to worry about someone climbing, falling, and breaking their neck.