Stacking rocks

Have the rock pets be able to stack on top of each other! It would just make the rock cooler and more unique in my opinion.

Pretty sure its not a dupe but if it is let me know! I did look for it, but I still feel like someone has made a suggestion about it.

How would it work, would it be like if you have a rock pet, and click on another one it has the option to stack it?