We just took our second camping trip in the 21RS and my 6 year old fell out of the top bunk.It was about 3 am. that we heard a thud and then crying. I flew out of the bed hopped the 85 lb. Lab in the floor and grabbed him in a matter of seconds. He didn't cry much and didn't seem to have a scratch on him. I am not sure he even woke up. He didn't even remember it in the morning. The next night we had him turn around and sleep with his head toward the window and behind the bathroom wall keeping most of his body protected from another roll-over. I still want to put up some kind of side rail. We have bunk beds at home that basically have a rail that slides between mattress and board. I remember seeing someone posted a picture of one they had. I believe it was a metal one that they may have bought. I may decide to just make something.