Why Do Dogs Smile?
The submissive grin is a tactic dogs use to shut off aggression from another individual, either human or canine. This behavior is commonly seen in greeting situations where the dog is actively soliciting attention in a nonthreatening manner. Often the submissive grin invites interaction from others, and it’s likely that your dog has continued “smiling” at you and your family because it’s gotten her a lot of attention in the past.
This is Ally, a 2 year old Lab/Collie mix who is available at www.outpaws.org- she has one of the best smiles we've seen!