I have had this happen a few times and was becoming concerned about the reaction Stella was getting from other dogs. To me she was lowering herself, not barking, not nipping, using appropriate doggy signals, apart from being a normal pup and being excited and overjoyed at seeing (anything) another dog. We have two other dogs, one of whom Stella is best friends with, been through puppy preschool, taken everywhere and exposed to other dogs on a very regular basis, so I could not work out why this was happening, and wanted to find out what I was missing. After a lot of conversation and observation I have come up with this - it seems Stella's natural stance and characteristics are at odds with her energy and behaviour. Think of an angry/aggressive dog, shoulders up and held, teeth showing, tail still and huffing, what does my sweet Stella look like? That dog. So put that together with the fact that a nose to nose meeting means getting closer than most other dogs and the loud breathing (huffing), I can see why a dog would be confused, therefore giving her the tensed up and warning growl. (which by the way Stella has totally ignores and keeps on wanting to kiss and play, which further confuses dog.) Dogs that are bigger tend to not be as reactive to Stella, medium and small dogs are the most unsure of her, so if I think of Stella from their perspective - teeth out, shoulders big, snorting, no tail motion approaching me and coming in a little to close for a smell, I get it. The other dog we have is not Stella's best friend, a 5 year old yorkie female Arabella. Arabella is not a dogs dog to be honest, but like a few posts has for no reason (it seems to us) just out of nowhere started a defensive exchange with Stella, is this because of the physical? Maybe I am way off, and would really like some input. I just want to make sure I am not missing anything that could turn into a problem.