Seven pets thread has made me curious so thought I would ask! In the last few months, when outside and someone walks past the garden (we have a 6 ft fence so its not people taunting) Piper has taken to barking. We think she learnt it from a friend's dog who does it when people are near their field. She also does it when out in the garden and the neighbours dogs are in their garden. Is this guarding? and how do I stop it, as its not helpful late at night when going out for a bed time wee!