They all have such adorable smiles, but my vote goes to the very first picture.....I love the little squinty puppy eyes. It doesn't get much cuter that that!
I have a dog polo shirt like that also, with the split in the back, I think they do it that way as not to interfere wth collars/leashes/harnesses as much. :)
and Thank you! I am going to see if Target still has anything similar... I LOVE that!