Books with author Mary-Ann Schmittzehe

Creature doesn't have a name. Certainly not one which springs to mind but decides he would like to have one. Enlisting the help of his good friend (a mole), Creature sets off on an adventure to find one. They cross over, into the human world where Creature discovers new friends in the form of children and, with the help of a friendly dog, manages to fend off a rather wicked cat. They must get back to their own world before their magic tunnel disappears.