Are you giving them grit as well. It is fine to let them have other things besides starter feed, but in order for them to process (digest) foods other than starter, they need grit. Saturn may have eaten too many seed/oats or even bedding and is now having trouble digesting. The white container(s) with the green bottom(s) are water and food I assume, you may want to raise those up out of the bedding, so it can be found easily.The floor is wool carpet covered heavily by bamboo leaves - they haven't made it down to the carpet. The feed is chicken starter feed - I grind it up. I also feed them some seeds and oats ground up. Sometimes some spinach leaves or a slice of cucumber. I'm worried as I haven't seen Saturn poo. The others poop fine, they are solid, sometimes squooshy though. Saturn both snuggles and separates herself from the others. She doesn't seem to sleep as much as the others either. I'll go take a photo now.
She is adorable, I hope she feels better soon.
All 3 are just cutie pies!