I had a male Aussie that would run out and sit next to the drivers side door of any car that drove in - He was all Smiles but No One would get out of their Car/Truck

The Bad one would sit at my side until I'd give him the word - then he'd jump on the hood and tear of the Wind-Sheld-Wripers

    with out her knowing it - I taught my wifes Min-Pin to hate the wifes Monther - She [the dog] had to be locked up when ever my Mother-in-Law came round.

I'd just say - 8) "how dog are such a good judge of people" :!: