Everyone knows that dogs are smart, but they mostly prove it when communicating to us, humans. But when they spend time together they usually act in a funny and relaxed way. However, it doesn't mean that animals lose their mental skills when put together - moreover, only in such conditions they show what they are really worth. And here is a great example of this statement. Look at this German shepherd - it only seems to be a simple dog, but when you tell him the secret words he comes and fetches his brother. And even if you think it's not that difficult to do, it does really look hilarious!