SDS is not only a dog thinking they are big, but thinking they are in charge. If your dog walks ahead of you, they thnk they're alpha. If a dog growls, they think they're alpha (or they are trying to take your place). If your dog nibbles, bites, or snaps at you, they think they're alpha. Luckily, I have cured Bailey of SDS, she used to bark, growl, nibble and lead me. I read something on
YorkieInfoCenter | Yorkshire Terrier Infomation Center about it (I think that was it...) and then I started working on it with Bailey. Part of her walking next to me was just in case a dog was out on his/her own (some even wander around on thier own) and attack.
Also, one of my incounters was when I was walking and Bailey just chased me around tge house! She wasn't big enough to get on the couch so I kept on just sitting on the couch with my feet up.
Or she'd attack my socks while I was sitting the and nibble my toes and bark when I moved my feet. Then she'd back up, attempt to fake out my feet, bark, attack, and repeat.