If you see cotton lie on them a lot Cotton may like them. If the rocks don't bite they may be friends, but not neccesarily bonded. Its like Rhino's and Birds. They tolerate eachother and work together, but there not best friends. It sounds like they may work together and tolerate eachother, so introducing more rocks may mess up there balance a little if its a larger rock as well. TLDR, sounds like they have a bond, but not friends, if that makes sense. Keep it up! Where did you buy or adopt them?
Oo, okay, tysm!
Hmmm, I kidnapped them from the beach!

























