My older boy of almost 3 went " Boom"! in the middle of the night and I knew right away that he had fallen from his bed. We just converted his crib to a toddler bed so it still has a half rail but the bottom half side is open. It was weird because an hour before, when DH and I went to sleep, I heard some bumping noise and DH says it was probable the neighbors (we live in an attached townhouse). I then admitted that I am always afraid that our son would fall off his bed someday and h did just that on that very night!! Poor thing was found on the floor sitting up in tears... he was so sleepy he was crying but still had his eyes closed....
Thank goodness he wasn't hurt - our first fall out of bed ended in a trip to the emergency room (stitches). We added bed rails after that and everyone was happy
Poor little guy. They are really resilient though. My kids had rolled down the stairs, climbed and fell out of the crib, and fell out of our bed. Just make sure there"s nothing around his bed that he cam bump into and injure himself. Maybe add a bed rail.
You can also stick a pool noodle under this sheet which creates a bedrail to keep them in bed. IT works very well and we use it all the time when we go to places to spend the night like a hotel/ MIL's house where cribs or toddlers beds arent' available. Easy and super cheap fix.