[Felina]

I have the same situation and I've put a small loveseat in front of the balcony railing with a large mexican print blanket draped over the actual railing looking down into the living room. They've never been curious to try and get behind the loveseat but they'd just have a blanket there if they did.

I also have a baby gate on the stairs so they are never up the stairs unless I'm right there with them each night when we all go up to bed.