My daughter and grand daughter have taught a few of mine to smile like that!
They smile when they see the 2 of them and I was lucky enough to get Reese on Camera smiling for me. My daughter just tells them to smile or says "Where's that pretty smile?" and they show them teeth! It is so cute!
She seems to be able to teach them anything, but they won't do anything for me (I guess they are just too spoiled). They know they don't have to do anything for treats

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