Exactly how much weight can a crib hold?

So the other morning I was doing the dishes before Katelyn woke up. Kelsey was upstairs playing in her room and evidently she heard Katelyn playing in her bed long before I did because when I heard them playing together, I just figured Kelsey was reading her stories like she does every morning before I get Katelyn out. It's kind of their little thing they do together and I love that they are both happy to see each other in the morning. However, on this particular day, it went a little different. Here's what I came up to.

So yes, while she was reading stories and playing with her, she was the crib with Katelyn. No wonder it was a half hour before I heard any cries or complaints and realized exactly how much time had really passed.

Now they both want out but can't get out so I figured I'd just leave them in there. Kelsey didn't figure out she was trapped until she was in and had no way out. We should have kept her in there as long as possible. Oh well. Hind sight is 20/20