I just watched oscar (male) do it.. He tries to stretch out and the lightbox tips and he falls.. so I think I'm paranoid lol. There going to the vets for a checkup anyway.
If they are falling off light boxes then maybe its because they cant get a decent grip on it,add to that the boxes are tipping....... Try some branches instead.
I just want to say everthing is ok, no diseases viruses etc. It had to do with lightbox grip and maybe a little dehydration.. they had a big drink and nothing has continued. thankyou to everyone who helped.