You did everything right with your pup. The endless puppy classes the careful introductions to new people and places the regular check ins at the vet. You might have even made dog park visits a weekly ritual or signed up for daycare on tough workdays. And just when you thought you had this parenting thing down your two year old dog starts growling at strangers snapping at other dogs or even nipping at your heels. You feel totally caught off guard. What went wrong? And why is