English KS1/KS2: Aesop's Fables - 9. The Dog, the Cockerel and the Fox
A cockerel and a dog live on a farm, where they are very good at their respective jobs – waking everyone up in the morning, and letting everyone know when there was someone at the gate. One day they decide to go on an adventure, although the cockerel needs some reassurance from the dog that it will be protected against foxes. At sunset they come to a wood, and find a hollow tree. The dog can sleep inside the tree, and the cockerel can roost in the branches.
The dog reassures the cockerel that no fox will find him in the tree unless he crows. However, in the morning the cockerel forgets himself and crows, attracting a fox, who tries to trick the cockerel into letting him up onto the branch. The cockerel tricks the fox in his turn, by saying that his porter will let him in at the bottom of the tree. The porter is, of course, the dog, who scares the fox away