Haopee, that was really cute. I wonder how they taught the dog to smile on command? It might have been during teeth brushing. Although, sometimes you can take something a dog does and turn it into a trick. The dog might have been doing this on its own, so the owner decided to teach it to do it on command. I did this with my dog. She was always jumping up and hitting people on their hands. So, I taught her "high five". Now she will do it on command.
Is smiling natural to dogs? I've seen my dog smile from time to time. It does appear that sometimes that smile comes when she is showing happiness.
