How do i change my new horses stable name?

If you do intend to change his name, it's best to change it to a name that doesn't sound like 'Wimpy'....like 'Blimpy'. Not that I think you'll change it to that, it's a horrible name..haha. That way your new horse will be better able to recognize the new name, instead of being confused over the name that sounds slightly like his old name.