hen I have them out the back and shes walking here from her mums house a couple streets away, they start barking and scratting at the back door knowing shes on her wayThe only thing I can think is they can smell her perfume, because the street she walks along is a full 3 houses away at the front and they are out the backyeah they are alot cleverer than we think!Mines the same, mum finishes work at