Susie my 12 year old yorkie has developed a habit of fighting with all the Small dogs we meet on a walk, she is fine with aany BIG dogs, she wants to play with them and runs around them and goes into the forelegs down "play with me" and the chasing off and wants them to play with her but only the big dogs, I am forever on the look out for the small dogs and being so tiny herself other dog owners expect her to be sooo sweet and good tempered when she is not, can anyone shed any light on why she is like this, she goes for mostly westies or yorkies and even s**t zu's and bechon friez, mostly any small dogs really???