I don't know, I find it a bit weird to have a wolf owning a wolf as a pet or a lion owning a lion as a pet or something. Maybe the pets could be a different type other than canine and feline, like lizard, tiny little deer or horse, or I'd definitely go for a little tiny dragon.
How would the commands work though? Maybe like Minecraft, where you type in /*insert command here* into the chat box or something. I do like this idea though ^^
moreideashere*cough* Maybe it can have certain skill levels and that you can train it and stuff, almost like the Sims where if you make it follow you and play with it it will gain a bar or something in the 'speed' skill and it will become faster. That would be cool. o3o