My first key book. Where is Farmer Bert?

Who can use the key to open the farm doors? Oskar the dog is excited: the postman has brought a package! He really wants to take it to the farmer. But where on earth is Farmer Bert? Oskar wants to look behind the many different stable doors on the farm to find him. He urgently needs the children’s help to do so. It’s a good thing that unlocking doors is so much fun and helps train fine motor skills at the same time.